This fudgy and ultra moist vegan chocolate zucchini cake is made in just one bowl and can be baked as either a sheet cake or layer cake. Topped with a rich dairy free chocolate sour cream frosting, this easy vegan cake is the best way to use up your zucchini!

slice of vegan chocolate zucchini cake

If you’re looking for a good vegan cake recipe to use up your summer zucchini, then you must try this decadent vegan chocolate zucchini cake. It’s like my vegan chocolate cake, but only more moist and chocolatey!

This chocolate zucchini cake recipe is also just one bowl, making it the easiest of summer cakes to make for a barbecue or summer party (just like my chocolate zucchini bread studded with chocolate chips that tastes just like cake- just in loaf form! You can even bake it into muffins or cupcakes instead!).

sliced vegan chocolate zucchini cake

And trust me, you won’t even be able to detect any hidden vegetables in this cake.

Make this zucchini cake gluten free as needed to make it even more suitable for all eaters!

Ingredients Overview:

Let’s go over the ingredients you’ll need for this vegan chocolate zucchini cake recipe:

  • Shredded zucchini: You can also use grated zucchini.
  • All purpose flour: You can also swap in gluten free 1:1 baking flour, such as Bob’s Red Mill in the blue bag. Please use the cup measurements, however, as that will be most accurate. Bob’s Red Mill is my preferred gluten-free flour blend. I DO NOT recommend using the Namaste flour blend.
  • Dutch-process cocoa powder: I like dutch-process cocoa powder for cakes over all other cocoa powders. It will also help our cakes to rise a bit better.
  • Dairy free yogurt: You can also swap in applesauce or pumpkin puree instead. This is my all time favorite vegan egg replacement to use in baking cakes, however. It’s so lovely!
  • Vegan buttermilk: This is just dairy free milk mixed with apple cider vinegar: I highly recommend soy milk, almond milk or pea milk here, as these will help curdle the milk more since they have more protein than other dairy free milks.
  • Vegan butter: You can also swap in coconut oil.
  • Hot coffee: The one ingredient to not have at room temperature! This is because hot liquid helps to bloom the cocoa powder even more, and coffee helps to amplify the flavor of chocolate. Use decaf or herbal coffee if you’d prefer!
  • Leavening agents: Of course, the baking soda and baking powder!
bitten into slice of chocolate zucchini cake on a cooling rack

Now, let’s get to work on this layered zucchini cake!

Overview: How to make chocolate zucchini cake

The cake

What is so wonderful about this chocolate zucchini cake is that you only need one large mixing bowl, a sifter, a whisk, and a silicone spatula.

You’ll start by whisking together the wet ingredients, including the zucchini. Then simply sift in the cocoa powder, followed by the flour, and the leavening agents. Add in the vegan buttermilk, and gently whisk together, followed by the hot coffee.

Then pour the batter into the cake pan. You can also use three 8″ cake pans or three 6″ cake pans. Bake the cake until a toothpick comes out clean. Then allow them to cool completely before frosting the cake.

How to make vegan chocolate sour cream frosting

For this vegan chocolate zucchini cake, we’re using a vegan chocolate sour cream frosting- based off of my classic chocolate frosting. It’s so easy to make and quite similar to making classic chocolate buttercream. But I think that the sour cream (dairy free, of course!) adds a really nice tang to balance out the sweetness!

You’ll need:

  • Vegan butter
  • Cocoa powder
  • Vegan sour cream (I like Forager Project)
  • Powdered sugar
  • Dairy free milk ​​​​

I recommend using a stand mixer with whisk attachment, but you can also use a hand mixer.

Tips for making Chocolate Zucchini Cake

Making a healthy chocolate cake is one thing, but making a healthy chocolate zucchini cake that you wouldn’t even know contained a speck of a vegetable?!

Now that’s another.

It’s definitely easy if you follow this recipe, but here are a few extra tips that I think really add to making the best vegan chocolate zucchini cake that even non-vegan eaters will go ga-ga over!

  • I recommend using a box grater to shred the zucchini. This will save you some arm work (and hopefully be bit safer!) than using a handheld grater.
  • Dry the zucchini before folding it into the vegan chocolate batter: If there is one thing you do, please please please make sure that you’ve pat the zucchini! It doesn’t have to be completely dry, but if it’s still leaving a paper towel sopping wet, it’s too wet. This is key for texture. Cassava flour generally likes moisture, but too much and you’ll get a gooey inside- not what you want for a chocolate zucchini cake!
  • Use coconut sugar for a refined sugar free chocolate cake and frosting! To do this, I pulse the coconut sugar in a mini food processor until it’s a powder. This takes about 2-3 minutes tops, and it fluffs up just like powdered sugar! It honestly makes for the ultimate Paleo chocolate zucchini cake.
  • You can make this a three layered or a two layered chocolate zucchini cake instead of a sheet cake: If you go for a two tier cake, I recommend using two 8-inch cake or springform pans.
sliced vegan chocolate zucchini cake

Every single person who tried a slice (we have many people who come through this house- kids, adults, friends, extended family!) was shocked when I told them that this healthy chocolate zucchini cake was indeed vegan and gluten free!

Let me know if you give this cake a go in the comments below, and as always, I’d absolutely love to see your beautiful recreations on Instagram and Pinterest, so be sure to tag me there!

Happy chocolate cake baking!

Want to save this recipe for later? Add it to your favorite recipe board on Pinterest!

One Bowl Easy Vegan Chocolate Zucchini Cake with Dairy Free Chocolate Sour Cream Frosting pinterest pin
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slice of vegan chocolate zucchini cake

One Bowl Easy Vegan Chocolate Zucchini Cake

5 Stars 4 Stars 3 Stars 2 Stars 1 Star 4.9 from 7 reviews
  • Author: Britt Berlin
  • Prep Time: 30
  • Cake cooling time: 60
  • Cook Time: 35
  • Total Time: 2 hours 5 minutes
  • Yield: 12 1x
  • Category: Dessert
  • Method: Baking
  • Cuisine: American
  • Diet: Vegan


This fudgy and ultra moist vegan chocolate zucchini cake is made in just one bowl and can be baked as either a sheet cake or layer cake. Topped with a rich dairy free chocolate sour cream frosting, this easy vegan cake is the best way to use up your zucchini!


  • 240 g grated zucchini, patted down to 170 g
  • 1 1/4 cup (300 mL) vegan buttermilk, room temperature
  • 1/2 cup (113 g) vegan butter, melted and cooled to room temperature
  • 1 3/4 cup (350 g) organic granulated sugar
  • 1/2 cup (100 g) brown sugar
  • 3/4 cup (170 g) dairy free yogurt, room temperature*
  • 3 cups (375 g) all purpose flour or gluten free 1:1 baking flour*
  • 1 cup (90 g) cocoa powder
  • 2 tsp baking powder
  • 1 tsp baking soda
  • 1 cup (240 mL) hot coffee or decaf coffee or herbal coffee

Chocolate Sour Cream Frosting:

  • 1/2 cup (113 g) vegan butter, room temperature
  • 1/4 cup (60 g0 vegan sour cream, room temperature
  • 1 cup (170 g) melted vegan chocolate, cooled to room temperature
  • 46 cups sifted vegan powdered sugar
  • 1/4 cup (25 g) cocoa powder


  1. Prep: Preheat the oven to 350F and line a 9×9 or 9×13″ sheet cake pan, or three 8 inch or  6-inch springform pans with parchment paper. Prep the zucchini and the vegan buttermilk. Set aside.
  2. Whisk: In a large mixing bowl, whisk together the vegan butter, sugar, brown sugar, and dairy free yogurt. Add in the zucchini, and whisk until combined. Then sift in the flour, along with the cocoa powder, baking powder and baking soda.
  3. Finish the batter: Add in the vegan buttermilk and begin to whisk all the ingredients together. Before the dry ingredients are fully incorporated, add in the hot coffee, and either whisk or use a silicone spatula to finish folding the batter until the dry ingredients are JUST incorporated. 
  4. Bake: Pour the batter into the prepared cake pans and bake the cake. For a 9×9 pan, bake for 50-55 minutes. For a 9×13 pan, bake for 40-45 minutes. For three 6″ cakes, it will take 45-50 minutes; for three 8″ cakes, it will take 32-35 minutes. The cakes are finished when the top is completely set and a toothpick comes out clean. Remove the cakes from the oven.
  5. Cool: Allow the cakes to cool in their pans for 10 minutes before transferring to a cooling rack to cool completely before frosting (about 1-2 hours depending on how warm your kitchen is).
  6. When ready to assemble: Once the cakes are cool, prepare the chocolate frosting. Cream together the vegan butter until fluffy, about 3 minutes. Then add in the sour cream, and mix again, followed by the melted and cooled vegan chocolate. Continue mixing until you achieve a consistent mixture. Then add in the powdered sugar in 2 cup increments, followed by the cocoa powder. Continue mixing until fluffy, stopping the mixer to scrape the bottom as needed. Frost the cake when ready!
  7. Slice and serve: Slice and serve your vegan chocolate zucchini cake. Store any leftovers in an airtight container and in the fridge for up to 5 days or in the freezer for up to 3 months.


Dairy free yogurt: You can also substitute in an equal amount of applesauce or pumpkin puree.

Gluten free: I recommend using Bob’s Red Mill gluten-free 1:1 baking flour in the blue bag. Use the cup measurements rather than the gram measurements for the gluten free flour blend.


  • Serving Size: 1 slice
  • Calories: 424
  • Sugar: 50.6 g
  • Sodium: 509.4 mg
  • Fat: 13.8 g
  • Saturated Fat: 3.1 g
  • Carbohydrates: 79.4 g
  • Fiber: 5.4 g
  • Protein: 3.9 g
  • Cholesterol: 0 mg

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