Absolute Best Tests

The Absolute Best Way to Make Pesto, According to So Many Tests

July  2, 2020
Photo by Ella Quittner

In Absolute Best Tests, Ella Quittner destroys the sanctity of her home kitchen in the name of the truth. She's boiled dozens of eggs, mashed a concerning number of potatoes, and seared more Porterhouse steaks than she cares to recall. Today, she tackles pesto.


Maurizio Valle makes a lot of pesto—about 100 batches each year, if he had to guess.

Valle, 77 and a Pesto World Championship finalist, lives in Genoa (the capital of Liguria and the capital of pesto) with a collection of 30-some mortars and pestles, including a few dating back to a 17th-century convent. The mortar he selects to demonstrate his signature technique over video chat is made of marble with four docks jutting out around its top, meant to remind the user to turn it every so often for the smoothest-possible pesto.

I got in touch with Valle, one of the “grandpas” featured in Vicky Bennison’s James Beard Award–winning Pasta Grannies, as soon as I knew I’d be addressing pesto for my latest round of Absolute Best Tests, suspecting he might have a hot take (or 10). But while his technique is wildly consistent across every batch he makes—mortar and pestle only; garlic first, then basil, then nuts, then cheese, then oil stirred in with a spoon—Valle has only one hard and fast rule when it comes to others making pesto: Don’t skip the garlic.

Photo by Ella Quittner

According to Saveur, the earliest recipe for pesto genovese—Valle’s specialty—appeared in Giovanni Battista Ratto's La Cuciniera Genovese in 1863. The word pesto itself, from “pestare,” meaning to crush in Italian, was apparently entered in Giovanni Casaccia’s Genovese-Italian dictionary in 1876. Nearly 150 years later, at least in the U.S., it’s become something of a catch-all for basil-based sauces made any number of ways: in a blender, in a food processor, with a half-moon rocking blade that will be seriously hard to fit onto your magnetic knife rack.

Join The Conversation

Top Comment:
“I have been making pesto this way for 50 years and it is the best pesto by far with a truly fresh basil flavor. Other options are to add 1 tablespoon of lemon juice so that the basil stays a bright green. You should try again with this method!!”
— Gigia K.
Comment

As it’s come to my attention that many of my city-dwelling peers lack a mortar collection like Valle’s, I tested a handful of the most popular ways to make pesto, to determine the pros and cons of each.


Controls & Fine Print

Ingredient ratios for basil pesto vary wildly across the web, with some calling for four times as many pine nuts as others. For each trial, I used a ratio close to Maurizio’s in Pasta Grannies, which I scaled way down per batch, as pine nuts are roughly the price of solid gold:

  • 1 clove garlic
  • 1/2 teaspoon salt (Valle calls for rock salt, to give you traction with the pestle; I used coarse kosher)
  • 3-ish cups basil leaves (if, like me, you can’t get the sweet, young basil grown in Prà that Valle swears by, he suggests looking for bunches with small, tender leaves)
  • 3-ish tablespoons Italian pine nuts, untoasted (in one round of trials, I’ll cop to having used walnuts in lieu of pine nuts—see the gold thing above—but I’m pleased to report that the swap produced an equally delicious, even nuttier pesto)
  • Heaping 1/3 cup grated cheese (a mixture of Parm and Pecorino; Maurizio calls for 4 tablespoons 18-month or older Parmigiano Reggiano, plus 1/2 tablespoon Pecorino Sardo)
  • 1/3 cup mildly flavored extra-virgin olive oil

In each round of trials, I tested seven ways to arrive at pesto:

  1. Mortar and Pestle
  2. Immersion Blender
  3. Mezzaluna
  4. Chef’s Knife
  5. Food Processor, Adding Basil Initially (pictured)
  6. Food Processor, Adding Basil at the End (not pictured)
  7. Blender

Key Takeaways

Mortar & Pestle

A mortar and pestle is the absolute best way to make pesto, which will be unsurprising to anyone who has had the pleasure of FaceTiming with a Pesto World Championship finalist. The resulting sauce was especially creamy, thanks to proper emulsion, and had the most basil-forward flavor of the bunch. Its oil barely seeped away from the pesto as it sat, and no single fleck or chunk remained decipherable when all was said and pestled. A few tips from Valle: Add the basil before the pine nuts, so the nuts can leech up any water released by the basil. Use a circular motion to blend the ingredients within the mortar (rather than an up-and-down pounding). And stir in the oil with a spoon rather than mixing it in with the pestle, so the wood doesn’t affect its flavor.

Click here for the mortar and pestle method.

Immersion Blender

I’m as shocked as a bunch of blanched broccoli to reveal that an immersion blender produces a sleeper-hit pesto—second in texture and flavor only to the mortar’s spoils. While plunging such a tool into a Weck jar of basil, pine nuts, and salt is awkward and unwieldy at first, the blades produce a much finer chop than either a standard blender or a food processor. And once you toss in grated cheese and oil, you’ll forget all about feeling like you’re excavating an oversized cavity. In discussing this unexpected success with Valle, Bennison, and Bennison’s colleague Livia De Giovanni, someone posited an interesting theory: The flavor might’ve remained fresher and sweeter than that of the other blended batches because an immersion blender’s motor is far above what’s being blended, unlike a food processor’s motor, a heat source that sits just below the contents.

Click here for the immersion blender method.

Hand-Chopping

Hand-chopping pesto is great in a lot of ways—it evokes the term “elbow grease,” and provides an excuse to ignore texts for 20 minutes—but it doesn’t produce the world’s smoothest pesto. Using a sharp blade, as on a chef’s knife or mezzaluna, to pulverize little bits of basil, garlic, and pine nuts until you can’t remember your own name does however create pesto with an interesting flavor. If mortar-pesto and immersion blender–pesto were the harmonious chorus of a quartet, hand-chopped pesto would be a song belted by a lead vocalist, supported by a guitarist, and punctuated by a sexy drummer who’s always taking two minute solos. (Garlic’s the hot drummer, keep up.)

Compared to the mezzaluna, the chef's knife helped me get the pine nuts and garlic a hair finer. When things in each batch got pretty close to mince-mode, the stubborn straggler pieces would scurry away from the mezzaluna’s blade as it came down on them, narrowly avoiding being chopped in two.

If you’re into a chunkier pesto and like to appreciate the individual flavor of each component, hand-chopping could very much be for you.

Click here for the chef's knife method.
Click here for the mezzaluna method.

Food Processor

I use my food processor for pretty much everything short of talk therapy, so am disappointed to report that it’s only good, not great, for making pesto. Its blades were able to achieve a decent mince, though it wasn't nearly as fine as that of the immersion blender. And while the oil initially appeared to be well combined, it separated from the solid components somewhat readily.

With this tool, I did two separate trials: One called for the basil upfront and cheese last; the other called for the basil after the cheese, nuts, and garlic had already been blended. Interestingly (this is interesting, right???), the basil-first batch had a better texture, a more even blend. Perhaps as Valle notes when describing his mortar method, crushing the basil earlier allows the nuts to absorb their liquid, creating a creamier mouthfeel.

Click here for the food processor (basil to start) method.
Click here for the food processor (basil to finish) method.

Blender

I used a vintage Osterizer blender for my trial, and I imagine things would’ve gone entirely differently with one of those hulking Vitamixes. As it were, my blender pesto was fine (as in, I dipped many tortilla chips in it for days to come and didn’t complain once), but had the least consistent chop of all the motorized methods. Which is not to say some components weren’t super fine—they were—it’s just that other components may as well have come from the hand-chopped batches. The blender also required double the volume of recipe for the blades to engage with the contents and, hello, have you seen the price of pine nuts?

Click here for the blender method.


Methods

Behold, all of the methods tested, in rough order of most to least delicious pesto produced. (I’d happily take any, for the record, if you’re thinking of having me over for a socially distant dinner. Please make focaccia too!) For ingredient ratios, check out the Controls & Fine Print section above.

Mortar & Pestle

adapted from Valle’s recipe in Pasta Grannies

  1. Use a mortar to crush garlic and salt into a paste.
  2. Add the basil, and move the pestle in a circular motion around the inner rim of the mortar to crush, rather than pounding it in an up-and-down motion.
  3. Add the pine nuts, and combine into the garlic and basil in the same way. Repeat with the cheese until you have a thick, bright paste.
  4. With a spoon—not the pestle—stir in olive oil.

Immersion Blender

inspired by this technique on My Food Story

  1. Place all ingredients, except the cheese and olive oil, into a jar slightly wider than the immersion blender. Blend as finely as you can, pausing to scrape out the inside of the immersion blender with a spatula or spoon every so often.
  2. Add the cheese and continue to blend, drizzling in the oil.

Chef’s Knife

adapted from 101 Cookbooks

  1. Use your sharpest chef’s knife to chop the garlic and a small handful of the basil leaves. Once the basil is in confetti-like pieces, add another handful and keep chopping. Repeat until you’ve chopped in all the basil.
  2. Once the basil and garlic is in a fine mice, chop in the pine nuts. Get those down to a fine mince, and chop in the cheese. By the time you’re finished, you should be able to use your blade to form a little block of pesto (sans oil) that will hold its shape.
  3. To turn this pesto cake into sauce, transfer to a bowl and stir in oil until combined.

Mezzaluna

adapted from 101 Cookbooks

  1. Rocking the mezzaluna back and forth, chop the garlic and a small handful of the basil leaves. Once the basil is in confetti-like pieces, add another handful and keep chopping. Repeat until you’ve chopped in all the basil.
  2. Once the basil and garlic is in a fine mice, chop in the pine nuts. Get those down to a fine mince, and chop in the cheese. By the time you’re finished, you should be able to use your blade to form a little block of pesto (sans oil) that will hold its shape.
  3. To turn this pesto cake into sauce, transfer to a bowl and stir in oil until combined.

Food Processor, Adding Basil Initially

adapted from NYT Cooking

  1. Add the basil, nuts, garlic, and salt to the food processor. Process until all ingredients are finely ground.
  2. Drizzle in the oil through the top spout as the motor runs, about a minute, or until the pesto is smooth and fully combined.
  3. Add the cheese, and pulse just to combine.

Food Processor, Adding Basil at the End

adapted from Bon Appétit

  1. Add the nuts, salt, garlic, and cheese to the food processor. Pulse until all ingredients are finely ground.
  2. Add the basil and start running the motor, drizzling in the oil through the top spout, about a minute, or until the pesto is smooth and fully combined.

Blender

adapted from this Genius Danny Bowien Pesto recipe

  1. Add the nuts, salt, and a bit of oil to the blender. Blend for a few moments until well combined.
  2. Add the basil, garlic, and remaining oil. Continue to blend until the mixture is smooth.
  3. Add the cheese and pulse until homogenous.
Photo by Ella Quittner

A Note on Basil & Pesto Storage

According to former Food52er Sarah Jampel, the best way to keep bunches of basil fresh is to store on the countertop with the stems in a bit of water, like a bouquet of flowers. (Marcella Hazan suggest this, too, in Marcella Cucina. She recommends keeping the basil somewhere cool, but not a refrigerator.)

If you’re not planning to use it immediately, you can cover pesto with a little extra oil and store in an airtight container in the fridge for a few days, or freeze it into cubes using an ice tray, then transfer to an airtight freezer bag for a few weeks.

What should Ella test next? Let us know in the comments, or send her a message here.

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See what other Food52 readers are saying.

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Ella Quittner

Written by: Ella Quittner

Ella Quittner is a contributing writer and the Absolute Best Tests columnist at Food52. She covers food, travel, wellness, lifestyle, home, novelty snacks, and internet-famous sandwiches. You can follow her on Instagram @equittner, or Twitter at @ellaquittner. She also develops recipes for Food52, and has a soft spot for all pasta, anything spicy, and salty chocolate things.

35 Comments

Mathieu G. July 18, 2020
Not sure if this was mentioned before but don't wash your basil leaves too much (like under tap water)! Use some slightly wet paper towel to clean the leaves.
 
Cbhall July 18, 2020
The trusty salad spinner works well for me for rinsing basil/other herbs.
 
scoot87501 July 18, 2020
This is way over thinking pesto. I have been making it for 30 years and I couldn't tell you where I got the recipe. I do make it in the food processor and it is delicious!
 
Cbhall July 18, 2020
Interesting article but I think I’ll stick with my food processor.
 
Rick G. July 17, 2020
I’ve been making and developing my pesto for over 25 years. I’ve always used a blender but I can imagine using a mortar and pestle would be excellent also. I’ve tried different nuts - cashews, pistachios, walnuts. I’ve tried toasting pinenuts I’ve tried different basil’s but the best is with sweet basil and pinenuts raw. I have recently changed from a strong Parmesan to a gran padano which doesn’t overwhelm the flavor like a Parmesan like Reggiano does. My recipe is based on weight and as long as I mostly dry the basil leaves it’s a pretty consistent and reliable method. Be very picky about your basil leaves and try not to use any stems and certainly not any of the flowers or the preflowering buds. I tried to use the lowest setting on the blender at all times and I start with the basil leaves, a generous amount of olive oil and salt. Then I add the garlic and the cheese and lastly the pinenuts and I try not to blend them very much because I like the chunkiness of various sizes of pine it pieces. I don’t like the flavor of overly blended basil leaves because it changes into some vegetal flavors which I don’t appreciate in this sauce I find that you can be overly generous with olive oil which will reduce oxidation when your pesto is being stored and you can just drain off excess without losing very much of the flavor. If your pesto includes cheese then you must be very careful about warming it up before you put it on hot pasta or gnocchi. My recipe is based on 100 g of basil leaves and if I harvest 180 g of basil leaves I just adjust the rest of the ingredients. And finally if anyone is interested in my recipe I’d be glad to share with them just send me an email at [email protected]
 
OldGrayMare July 17, 2020
This has nothing to do with HOW to make pesto, but in summer, I love making one with fresh dill....put on plain canned chickpeas. Think found recipe from Food52...whatever, its like the smell of fresh mown grass!!
 
Gigia K. July 10, 2020
None of these methods are the one I learned as a small child, where I grew up eating pesto as taught to me by my mother’s family who settled in San Francisco from Liguria.

The most important difference, the cheese does not belong in the pesto! Pest is made of just basil, garlic, olive oil and salt. The best way I have found to make it besides the mortar and pestle is in a VitaMix because it breaks down the plants cell walls and makes one smooth flavor out of the ingredients.

The cheese and/or nuts are added into the pasta with a splash of hot boiling water at the end. Otherwise the cheese may melt into globs and the pesto will not coat the pasta smoothly.

I have been making pesto this way for 50 years and it is the best pesto by far with a truly fresh basil flavor. Other options are to add 1 tablespoon of lemon juice so that the basil stays a bright green.

You should try again with this method!!
 
Linda B. July 10, 2020
Absolutely agree on the lemon juice. Green pesto is much more beautiful than brown.
Do you leave the pine nuts whole?
 
Gigia K. July 10, 2020
I roughly chop them and then add them in when I add the cheese. Sometimes substitute walnuts for pine nuts. When we were little and Italian Food wasn’t trendy we had to use walnuts and Dry Monterrey Jack cheese.
 
Gigia K. July 10, 2020
Another thing about using a blender. It can have a great texture, but has to be done in a specific way. Start with the garlic, lemon juice, olive oil and salt and a small amount of basil leaves. Get a loose paste going first, then slowly add more leaves. If it gets too thick again, then add more oil. Don’t blend too long or the basil will get hot and turn brown.
 
Lois R. July 5, 2020
Basil is incredibly easy to grow! I live in an apartment and set pots underneath a grow light. You can order seeds for many varieties, including Genoese basil. While basil is happiest growing outdoors in bright sun, it grows well if a bit more slowly indoors.
 
Susan D. July 5, 2020
Just one question, please...

I found this Pesto article via a link in an email from Food52 dated 7-3-2020.

The problem/question is that the email says this is a link to "The Absolute Best Way to Make Pasta Dough, According to So Many Tests".

Pasta Dough -- Not Pesto!!

Not only did I read most of the entire page but, as a backup, I did a search for the words "Pasta Dough" on this page. They were nowhere to be found!!

Where is the article about making Pasta Dough?? Does one exist?

I've made homemade pasta many times but, I received a new pasta maker as a gift recently, which I'm really looking forward to trying out! So I was hoping to find info here about making Pasta Dough, not Pesto!

Any help will be greatly appreciated! And if you have a link to the correct page for making Pasta Dough, I would appreciate that even more!!

Thank you!
 
Joyce July 5, 2020
I thought I had mis-read it! It does say pasta! Here’s a link to a pasta recipe from this site... https://food52.com/recipes/83340-semolina-pasta-dough-recipe
 
Susan D. July 5, 2020
Thank you so much, Joyce!
Very much appreciated!

I was actually horrified when I landed on this page! While I love using fresh basil, I really don't like pesto, nor does my very-Italian husband!

Perhaps that's a bit odd considering neither of us are picky eaters but, we will always prefer a hearty tomato sauce or alfredo over pesto any day!

Thanks again for the link! There is some good info on that page.
 
Diana M. July 3, 2020
I grow 5-6 basil plants in a planter on my balcony every summer, and harvest the leaves 2 or 3 times over the season. I freeze the pesto in those wee little glass canning jars (4 oz., I think). They make lovely gifts. As for measuring the fresh basil, I pile as many leaves as I can into a 2-cup measure, pushing down a bit. When I release my hand, it tends to pop back up, and some leaves fall out. Anything that stays in the measure goes in that batch. Close enough!
 
Smaug July 4, 2020
I usually just grab a handful, and decide how much I'm going to use after I chop it, or whatever's ready to cut if I'm going to freeze it. However, if you're going to do a side by side test of a made dish, you need considerable more uniformity of ingredients. I usually do 3 or 4 crops during the summer- it's very easy from seed, the seeds are cheap, and the flavor is so much better with young plants.
 
Helen S. July 3, 2020
The primary reason the food processor didn't mince well was a dull blade. Most people never buy a new S blade for the processor producing poor results. If you mince the basil (with a sharp blade) first, then add everything but the oil. Add only enough oil to bind it together. At 120 calories a tablespoon, you don't have to add 600 calories to it.
 
Linda B. July 3, 2020
If I am planning on consuming all of the pesto I make I add the cheese but if I'm planning on freezing some I omit the cheese, add enough oil to thoroughly coat all of the basil, garlic, pine nut mixture and freeze in small containers or ice cube trays. I then add the cheese and the rest of the oil once the frozen mixture has thawed. I do it this way because I find the taste of the frozen and then thawed parmesan to be rather unpleasant and stale. Cheese does not freeze well in my experience.
I make massive quantities of this mixture during the summer so that on a winter's night when I am craving pesto I have lots on hand. It's not as good as fresh but it is good enough to satisfy this pesto fan when there is no fresh basil to be found.
 
Maria K. July 2, 2020
I find that pecans produce an excellent pesto, very close to pine nuts and much superior to walnuts.
 
Stephanie G. July 4, 2020
Yes! I use pecans exclusively now too. They are cheaper and I always have them on hand.
 
Mathieu G. July 18, 2020
Sunflower seeds are also a cheaper alternative and are really giving a nice twist!
 
Stephanie G. July 2, 2020
I use the hand chopping method. It's the way I learned from Deborah Madison's Vegetarian Cooking for Everyone.
 
Maurizio L. July 2, 2020
This wonderful post finally pushed me to order that Italian mortar and pestle I've been coveting for years -- just like my nonna's from Carrara. Excited to give it a try once it arrives!
 
Tim Y. July 4, 2020
Where did you purchase? I am looking for one and would love a recommendation.
 
pgarratt July 5, 2020
As a pharmacist married to a chemist I have a small collection of mortars and pestles which are priceless tools in my kitchen. I have a smallish marble one which is great but has too little space to get great emulsification. My go to is a granite mortar and pestle dragged home in my back pack from Vancouver Island to Ontario. It’s surface never stains nor takes up flavours that might effect the next product. It also has a rough enough surface to make the process really easy. It is heavy and indestructible... so far! Much less permeable than marble and perhaps less pretty than marble! Mortars and pestles are the best !
 
Maurizio L. July 5, 2020
Found it on Etsy from an Italian source near Carrara!
 
gandalf July 7, 2020
Did you order your granite mortar and pestle when you got it, or get it in a store? Do you know the brand/manufacturer?
 
pgarratt July 7, 2020
Met an artist working with his family. They beachcombed the granite and turned them into table top candle hold mortars and pestles. Etc. I will look for contact information and post it. Pam
 
gandalf July 7, 2020
Thanks so much!
 
pgarratt July 8, 2020
There is one available from Williams Food Equipment called Fresco granite sloped front which I have as my go to mortar and pestle in my kitchen. Rough enough surface but cleans well. Pam
 
gandalf July 8, 2020
Thank you again!
 
Holly H. July 2, 2020
Love to read about pesto and happy to see your comparisons. I want to comment on pine nuts as it is an essential ingredient. Some people may have a reaction, commonly called “pine mouth” which is most unpleasant and I’d hate to think one might blame it on the basil or spoiled olive oil. The most common pine nut sold in the US is from China and it is thought that the particular pine tree species in China causes the malady. There are alternatives tho not as readily available but it is worth the search (and price). Google New Mexico pine nuts for a source to purchase. They are truly excellent, far superior to those from China in appearance and flavor/texture. There are also Italian/Mediterranean pine nuts which are an alternative to Chinese. This is no slander of items of Chinese origin (so many delicacies and objects). It’s just that in the case of pine nuts, in my opinion, there is a superior alternative.
 
Maurizio L. July 2, 2020
I live here in New Mexico and can attest to having wonderful pine nuts!
 
Smaug July 2, 2020
The basil would seem to me to have some inherent problems for a comparison test. For one thing, measuring leaves by volume is pretty hopeless, and weight is no better since the moisture content (and possibly the leaf to stem ratio) can vary so much. For another, the internal chemistry and flavor of basil changes rather radically as it enters and progresses through the flowering process, and commercially available basil has almost always at least begun to bolt.



















 
Stevie T. July 4, 2020
Question: My Cuisinart immersion blender came with a 500mL/2 cup plastic vessel abou the size and shape of mason jar. Is there any chance that it will impart a plastic taste to the pesto. (I'd likely be freezing the pesto right away.)