Japanese Basics: Kelp Stock and Dashi Stock

March 22, 2013

Every week, a DIY expert spares us a trip to the grocery store and shows us how to make small batches of great foods at home.

Today, Hiroko Shimbo, author of Hiroko's American Kitchen and The Japanese Kitchen, shares two stocks that will make Japanese cooking a reality in all of our kitchens. Add umami to your soups and sauces with Kelp Stock and Dashi Stock, and be sure to pick up Hiroko's favorite Japanese ingredients in our shop!

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The first step to cooking easy, accessible Japanese food in your kitchen is preparing the two basic stocks that form the foundation of many Japanese dishes: kombu dashi (kelp stock) and dashi (kelp stock infused with dried fish flakes).

With a few batches of these stocks in your refrigerator or freezer, your favorite miso soup or noodle broth is just five minutes away. Kelp stock and dashi stock are also ideal for preparing American dishes with a healthful and delicious Japanese touch; they make wonderful substitutes for meat, chicken and Western vegetable stock. 

The simplest stock is kelp stock, or kombu dashi. For this recipe, I use shredded ma-kombu kelp from Japan, which produces the most flavorful stock and is easiest to store.

I recommend preparing this broth at night; it takes two minutes, and the kelp soaking in water will create a beautiful stock while you are sleeping! 


Simple Kombu Dashi (Kelp Stock)

Makes 8 cups

8 cups cold water
1 ounce kelp (if using ma-kombu, reduce the weight to 3/4 ounces) 

See the full recipe (and save and print it) here.

Fill a large, clean bowl with 8 cups cold water. Add your kombu, cover the bowl with plastic wrap, and store it in the refrigerator overnight, or for about 10 hours. If using sheets of kombu, wipe them with a moist, clean kitchen towel to remove any impurities, then cut them into small pieces.


Once the kombu has soaked, strain the stock through a fine mesh strainer set over a large bowl or jar. I line the strainer with a moist paper towel so that none of the kelp particles get into the stock. Reserve the kelp for a second stock preparation. 

Your stock should be full-bodied, with a faintly sweet and salty taste. For the best flavor, use within three days, or freeze what you won't be using immediately.

You can make a second stock by placing the used kombu and 6 cups of water in a large pot and bringing it to a gentle simmer over medium heat. Decrease the heat to medium-low and cook for 15 minutes, then strain through a paper towel-lined sieve. The second stock is somewhat weaker in flavor than the first stock, but it is perfect for making soup and braising fish, poultry, or meat.


Note: Kelp that has been used twice should never be thrown away. I like to make a simple condiment with mine: simply cook strips of kelp in a pot over medium-low heat with a little water, a little sugar, a little soy sauce, and a little rice vinegar until most of the liquid is absorbed. At the end of cooking, add some chili powder. Use to garnish salad greens, noodle bowls, or even bagels and cream cheese!


Now let's move on to the dashi preparation. Dashi is a must-have stock in the Japanese kitchen. It is the base of everyone's favorite miso soup, udon and soba noodle broth, ramen broth, and ponzu sauce.

To prepare dashi stock, you simply bring kelp stock to a gentle simmer and add dried fish flakes. People often call these flakes "bonito" fish flakes, but the type of fish used is actually skipjack tuna. When you purchase dried fish flakes, look for flakes that are glossy and light in color. 


Flavorful, Almighty Dashi

Makes 7 1/2 cups

8 cups prepared kelp stock
4 cups (2 ounces) katsuobushi (dried skipjack tuna fish flakes)

See the full recipe (and save and print it) here.

Place the prepared kelp stock in a large pot over medium heat and heat up to 175° F. Add the fish flakes all at once, gently pushing the flakes down into the stock with a spatula. Wait for the stock to come to a gentle simmer, and then quickly turn off the heat. Leave the fish flakes in the stock for about 5 minutes.

Strain the stock through a strainer lined with a moist paper towel, ensuring that none of the fish flakes pass into your stock. Dashishould be very clean and clear; it will be much more flavorful than kelp stock. For best results, use it within three days, or store it in the freezer for later use.

Looking for the best Japanese ingredients? Find Hiroko's pantry essentials in our shop! And for more ways to use dashi and kombu dashi, turn to Hiroko's latest book.

Photos by James Ransom 

See what other Food52 readers are saying.

  • OhMisha
  • Karen
  • anne
  • tamater sammich
    tamater sammich
  • LeBec Fin
    LeBec Fin
I am an authority on Japanese cooking and author of "Hiroko's American Kitchen" and "The Japanese Kitchen."


OhMisha July 31, 2018
Just a note: The link to the Japanese pantry essentials is broken
Karen October 8, 2014
As much as this sounds good Fukishima is still leaking like crazy and there are many of us who know well enough to never eat anything from Japan and the northern Pacific. It is a shame but a necessity to know where food comes from nowadays.
anne August 8, 2013
Thank you for this, Ms. Shimbo. I live in Berkeley, CA and have a wonderful Japanese fish market nearby. I have always wondered about all of the mysterious ingredients on the shelves, and in bins, and now I will be able to go by kombu and katsuobushi with great authority! Can't wait to make some delicious miso soups!
tamater S. March 25, 2013
Thanks for the simple recipes. I'm always looking for lighter, clean tasting fare. I'll check out your cookbooks.
Hiroko S. April 11, 2013
Thank you! I would like to let you know that Hiroko's American Kitchen won the Finalist Award at IACP cookbook of the year under American cookbook category!
LeBec F. March 25, 2013
hiroko, this is terrifically helpful,so thx so much! i do have a few questions.
- why refrig the kombu steeping? does the cold help in the extraction? i can't imagine that doing this at room temp would be dangerous, healthwise, as seaweed is seaweed, and i might imagine that room temp might be more effective than cold- in extracting flavor....

-- i have always read that the katsuobushi step should only be five minutes, but when i follow that, i do not yield enough flavor (for ME that is). So i slways leave it longer and have even simmered it for 1/2 hour- and yielded a more flavorful base.(I don't care about the clarity of the dashi, just the flavor; again, this is just for me). Have you experimented in the ways i have and what has been your experience?
thx so much. i've always wanted to ask these questions.
Hiroko S. April 11, 2013
Please forgive me my belated reply to your question. I was in Japan, leading my culinary tour. Here is the reply. Room temperature spoils the kelp in tap water. (Kelp grows in salt water.) Next reply: steeping katsuobushi for half an hour produces strong flavored dashi. If you like that taste, it is fine. Over soaking of the katsuobushi in hot water, though, produces some bitterness and too fish flavor in the stock. For us, dashi should be clear clean. If you like your version, please stay with it! By the way Hiroko's American Kitchen won the Finalist at IACP Cookbook Award under American Cookbook category.
walkie74 March 22, 2013
Wait..that's it? And I've been buying concentrated dashi stock all this time?!?! Never again!
Marian B. March 24, 2013
It's so easy!
bonbonmarie March 27, 2013
I know! I read somewhere once that "making dashi is complicated process, best to buy the concentrate". HA! I found a remainder book called Japanese Home Cooking which demystified this totally non-mysterious process. I will try Hiroko's method too, which is a bit different from mine.
Hiroko S. April 11, 2013
Today there are naturally produced concentrated dashi available. But, the most sure thing is to make your own dashi with kelp and katsuobushi, dried fish flakes. You get natural nutrients from these ingredients and real flavor.
Greengourmet March 22, 2013
Thank you for this post! As a vegetarian soup lover, I've been searching for a flavorful broth alternative. The kelp broth sounds healthy, easy, and delicious!
David N. March 25, 2013
It's Fish!
Kristen M. March 25, 2013
The kelp broth doesn't have fish in it -- just the dashi does. I've tried vegetable soups made with this kelp broth and they are shockingly good.
Hiroko S. April 11, 2013
For a vegetarian preparation KELP STOCK is the answer! Healthy, easy and delicious!
Hiroko S. April 11, 2013
Well, kelp is not Fish!
Hiroko S. April 11, 2013
Kristen, find some additional shockingly good vegetable soups in Hiroko's American Kitchen. The book has recently won the Finalist award of IACP cookbook of the year under American cookbook category!
David N. April 11, 2013
Sorry.. missed the Kelp broth. Was focused on the Dashi.
Hiroko S. April 11, 2013
No apology, please! I love Dashi stock which has diverse use.