Dark Chocolate and Walnut Zucchini Bread

August 20, 2015
19 Ratings
Photo by James Ransom
  • Makes 1 8 1/2 x 4 1/2-inch loaf
Author Notes

Despite its appearance and ingredients list, this zucchini bread, adapted from the Seven Spoons cookbook, is surprisingly not too sweet.

It gets its rich flavor from a generous amount of bittersweet dark chocolate, chunked into the batter. The chunks melt into the base of the bread so that you get damp, oozing, and warm pockets of chocolate throughout... as well as some additional darkness from Dutch process cocoa powder.

The zucchini, though, is the main star. The pieces give a hearty texture, moistness, and depth to the bread. Added walnuts yield a delicious buttery taste and toasty aromatic flavor that pairs perfectly with the dark chocolate and zucchini. —thalia ho

Test Kitchen Notes

WHO: Thalia is a self-taught baker from Australia who writes the blog Butter and Brioche.
WHAT: A dense, fudgy, not-too-sweet tea loaf that's packed with zucchini (even if it doesn't taste like it).
HOW: Fold walnuts, shredded zucchini, and lots of bittersweet chocolate chunks into a cocoa-buttermilk quick bread, and sprinkle more chocolate chunks on top.
WHY WE LOVE IT: This quick bread is extremely chocolatey—with nary a hint of zucchini flavor! But aside from the melty chocolate on top of each slice, the zucchini is the best part of this loaf: It makes it extra moist, from the moment it comes out out the oven to the next day, when you sneak a slice for breakfast (it has vegetables in it, right?) —The Editors

What You'll Need
  • 2 1/2 cups grated zucchini
  • 3/4 cup all-purpose flour
  • 3/4 cup whole wheat flour
  • 1/4 cup Dutch process cocoa powder
  • 3/4 teaspoon baking soda
  • 1/2 teaspoon baking powder
  • 1 teaspoon sea salt
  • 1/2 cup walnuts, chopped and toasted
  • 1 1/4 cups bittersweet dark chocolate (at least 70%), chopped
  • 1/4 cup unsalted butter, melted
  • 1/2 cup buttermilk
  • 1 large egg
  • 3/4 cup light brown sugar
  • 1 teaspoon vanilla extract
  1. Preheat an oven to 350° F (175° C).
  2. Grease and line a 8 1/2 x 4 1/2-inch (21 x 10-centimeter) loaf pan and set it aside. Let the parchment paper hang over the sides.
  3. Place the grated zucchini on a baking tray lined with a lint-free kitchen towel, then place another kitchen towel on top, patting it down gently to absorb any additional moisture. Set aside.
  4. In a large bowl, use a fork to whisk together the flours, cocoa powder, baking soda, baking powder and sea salt. Stir in the chopped walnuts and 1 cup of the dark chocolate.
  5. In a separate large bowl, whisk together the butter and buttermilk. Add in the egg, light brown sugar, and vanilla, then whisk the liquid ingredients until smooth and uniform. Gently fold in the zucchini.
  6. Pour the liquid ingredients into the dry ingredients and stir until just combined.
  7. Pour the batter into the prepared loaf pan, then sprinkle the top of the batter with the remaining 1/4 cup of chopped dark chocolate.
  8. Bake, rotating at least once half way through baking, until a skewer inserted into the bread comes out clean, 50 to 60 minutes.
  9. Let cool in the loaf pan for 15 to 20 minutes before inverting out onto a cooling rack to finish cooling completely.

See what other Food52ers are saying.

  • Kathy Sobb
    Kathy Sobb
  • Jess
  • Nicole S. Urdang
    Nicole S. Urdang
  • Niki Checketts
    Niki Checketts
  • Yogigirl

47 Reviews

Chez.Chel October 11, 2023
I live in Connecticut USA so I bake it in zucchini harvest (and grocery discount) season. Just 2 cups of zucchini is the sweet spot, more gives you a texture problem. I typically use the flour I have on hand, organic white, although solid idea to use some whole wheat to boost nutritional value. Most don't keep buttermilk in our fridges, but it's worth the extra cost and shopping trip. For those who love mildly sweet baked goods, it may be the magic ingredient. My family is in love with this bread: TY Food52 and Thalia Ho for this recipe!
Kace S. February 3, 2023
This was great and easy to put together. I used scant 1/4C whole milk yogurt to make my 1/2C buttermilk, subbed pecans for walnuts, and was thwarted by a lack of zucchini so I used a parsnip and two carrots instead. Delicious! It baked up in 50 min at 350F and tested done with a toothpick. Easy-peasy.
valerieohm June 19, 2023
do you know how much chocolate (in weight, not volume) is needed?1 1/4c is how many grams (or ounces)?
EricaDee July 24, 2022
I don't know why there are so many negative reviews. This cake came out moist and chocolatey. I did do a couple of substitutions since I made this on a whim... watered down greek yogurt in place of buttermilk, white flour for the whole wheat and semi-sweet chocolate for the bittersweet. :)
Akané September 26, 2021
I wanted all the negative reviews to be wrong because it sounded yummy so I made this anyway but I must say they were right!
Unfortunately the only ingredient that shouldn’t be in this was zucchini, it gave a strange texture, very inharmonious.
Akané October 6, 2021
Actually it turned out to be much more enjoyable once it was chilled next day!
Raye A. September 24, 2021
Delicious. Rich and chocolatey. I added a pinch of cinnamon. Do not expect it to rise too much since it only has one egg and not much baking powder. It is dense with chocolate, but I like that. If you want a more light and airy zucchini bread this is not the recipe for you. I used two medium zucchini.
Kathy S. January 10, 2021
What a waste of chocolate! Followed this recipe carefully. End result is mushy, and most of chocolate taste is overpowered by the zucchini. Don’t. Just don’t.
Jess August 23, 2020
I am trying my hand at vegetable gardening for the first time this summer. I have costar romanesco zucchini threatening to drown my household. So that's what I used to make this. I recommend using a high quality cocoa powder and chocolate. I brought this to work and people asked for the recipe.
Melissa July 25, 2020
First let me say that I love zucchini and am currently up to my ears in it. I’ve been testing different zucchini breads and expected this to be great. Unfortunately it was not balanced at all - I think there’s way too much zucchini in it and it’s overpowering. My favorite so far has been the Olive Oil Zucchini bread by Melissa Clark in the NYT.
LionToes May 1, 2020
Want to make this tomorrow (finally have all the ingredients after a ten-day grocery delivery wait time!)
But — Have a question! I only have whole wheat bread flour. Can I sub 1 for 1 with required whole wheat flour? May seem an obvious question but concerned the added protein/gluten in the bread flour might mess things up. Hoping for a timely reply, thanks!
lgh07 August 12, 2019
OOoooohhhh it's soo good!!!!
Esther October 24, 2018
Well... didn't appeal to us.... We love all the ingredients... But seemed way over the top chocolatey... We ate it, but I would not make it again.
joanbartz August 31, 2018
I made this last night, and it's a delight! I used white sugar instead of brown, powdered reconstituted buttermilk because it's what I keep around, grated zucchini from day prior, milk chocolate chips instead of dark, and Trader Joe's cocoa (not sure if it's Dutch). The loaf baked for exactly 65 minutes and it is so moist and delicious. Love that the recipe was able to handle my substitutions - this is my kind of recipe! Thank you for such an easy delicious cake!
jean C. August 21, 2018
Would this work as muffins?
Donna February 5, 2018
I followed the recipe exactly, but did not really care for the results, nor did several other adults who tried it. It seemed to have an identity conflict.
Nicole S. January 14, 2018
Is there a non dairy substitute for buttermilk?
Lisa L. January 14, 2018
You could probably sour some soy milk/almond milk with lemon juice or vinegar, mix, and let it sit for 5-10 min (until slightly curdled) before using.
Nicole S. January 14, 2018
Thank you! That’s exactly what I was thinking. Just thought there might be another alternative I was missing.
DebS January 13, 2018
This is fabulous! It came together so quickly and easily. I didn’t have walnuts and also wanted to be able to send to my kids’ nut free school so I substituted cocoa nibs instead. So yummy, I will definitely make this again.
Oaklandpat September 29, 2017
Can anyone tell me how many zucchini you need to end upon with 2 1/2 cups grated? I have 3 medium size ones that need using up.... will that be sufficient?
ghainskom September 29, 2017
Yes that should do. If not I'd fill up with carrots or even apples...
Raye A. September 24, 2021
I used two medium sized zucchini and it was just right at 2-1/2 cups.
Niki C. August 30, 2017
Love love love! This was absolutely fabulous. The only changes I made were to swap out walnuts for toasted pepitas (I know, I know - totally different. But what's a girl to do when she's craving chocolate with a crunch?). That sent me down a Mexican-inspired train of thought, so I also added cinnamon and cayenne. Holy guacamole was this good.
Yogigirl August 20, 2017
I used nestle cocoa powder and siggi's drinkable vanilla yogurt (instead of buttermilk) because that is what I had on hand. Threw in some unsweetened coconut flakes and baked it up. So yummy! (And I agree, not overly sweet)
Lisa L. August 17, 2017
Could natural cocoa powder be substituted in this recipe?