Tessa’s Recipe Rundown
Taste: Ultra chocolaty! I doubt any kids would guess there’s a vegetable involved here.
Texture: Rich, fudgy, and moist.
Ease: Super quick and easy. No mixer, no assembling, no decorating.
Pros: Simple summer treat!
Cons: None 🙂
Would I make this again? Absolutely, all season long.
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We’re about to head into the height of zucchini season, which is just one of the many reasons you’ll adore this Chocolate Zucchini Cake.
I love getting fresh zucchini from the farmer’s market all summer long. It’s one of those veggies that’s so easy to cook and bake with. You can find a million ways to get creative whether you’re going savory or sweet. And it doesn’t take nearly an hour to cook like root veggies.
Adding zucchini to cake happens to be one of my favorite ways to use the stuff. I also enjoy a good zucchini bread, like this Lemon Yogurt Zucchini Bread.
I love snack cakes like this recipe because they’re just one layer, and there’s no assembly or decorating required. They’re also super easy to transport. You don’t even need an electric mixer for the batter or the icing here!
That makes this recipe perfect for bringing to a summer potluck or BBQ. Especially if you have an abundance of zucchini to use up!
I find many chocolate zucchini cakes to be kind of bland and a little dry. Read my tips below for getting a super rich and fudgy cake with tons of chocolate flavor.
This might just become your new favorite zucchini recipe!
Sprinkle of Science
How to Make Moist Chocolate Zucchini Cake
The Best Cocoa Powder for Chocolate Cake
Cocoa powder lends more chocolate flavor than melted chocolate. But it can also zap some moisture, so read my tips below for how to make sure your cake is nice and tender and moist. This recipe uses natural unsweetened cocoa powder (not Dutch process cocoa powder). Learn more about cocoa powder here.
For best results, weigh your cocoa powder and flour to ensure you don’t over-measure. This will result in a dry cake. If you don’t have a digital kitchen scale, then use the spoon-and-level method.
How to Shred Zucchini for Cake (IMPORTANT!)
To avoid gummy, dense, or unbaked Chocolate Zucchini Cake, it’s important to remove as much excess water from the zucchini as possible.
- Start by washing the zucchini and trimming the ends. Grate using the big holes of a box grater. Scoop up the shredded zucchini and place in a strainer or colander. Move on to prepare the rest of the ingredients and batter for the recipe.
- Once you’re ready to add in the zucchini, wrap it in a clean towel or paper towels and give it a very tight squeeze with your hands to wring out excess water. Do this a few times. If your hands aren’t quite strong enough, you can also press the zucchini inside a potato ricer or hand-held citrus squeezer. This is super effective at getting rid of water.
- Once you fold in the zucchini to the batter, stir gently until JUST combined. Over-mixing can cause a tough or gummy texture.
Why Use Butter AND Oil in a Cake?
- I find this provides the best of both worlds.
- You get the wonderful flavor from the butter and the moist texture from the oil.
- This is because oil is a liquid at room temperature so it gives your palate the sensation of moisture.
- Learn more about Butter vs. Oil in Baking here.
How to Bake a Moist & Fudgy Chocolate Cake
- In addition to the tips above, using ingredients like brown sugar, full-fat sour cream, and an extra egg yolk all help to add richness and moisture to this cake.
- That’s because these ingredients both tenderize and draw and hold onto moisture.
- You can learn more about how baking ingredients work in my Magic of Baking online class.
Can I Substitute the Sour Cream?
You can use full-fat plain yogurt instead!
What Type of Chocolate Chips Should I Use?
I used semi-sweet chocolate chips, but you could experiment with milk chocolate chips, mini chocolate chips, or even white chocolate chips, if you prefer.
Is it Better to Bake a Cake in a Glass or Metal Pan?
- This recipe is best baked in an 8-inch metal baking pan.
- Metal conducts heat more quickly and efficiently than glass or ceramic so you won’t have any issues with an under-baked center.
- If you must use glass or ceramic, reduce the baking temperature to 325°F and increase the baking time by 5 to 10 minutes.
- Learn more about Glass vs. Metal Baking Pans in my article here.
Frosting for Zucchini Cake
I used a simple icing for this Chocolate Zucchini Cake recipe, but you could also use my cream cheese frosting or even this chocolate frosting.
Can I Double this Recipe?
Yes! Double all ingredients, bake in a 9 by 13-inch pan, and add about 5 to 10 minutes to the baking time. If using glass, see note above.
How Long Does Chocolate Zucchini Cake Last?
This Zucchini Cake can be stored in an airtight container at room temperature for up to 4 days.
Can You Freeze Chocolate Zucchini Cake?
- Freeze individual slices on parchment paper for about 15-30 minutes, then wrap each in plastic wrap and place in an airtight container.
- Defrost in the fridge or on the counter and let come to room temperature before enjoying.
- I recommend freezing the cake unfrosted.
More Recipes You’ll Love:
- Chocolate Zucchini Bread
- Best Ever Chocolate Cake
- Chocolate Bundt Cake
- Easy Chocolate Sheet Cake
- Flourless Chocolate Cake
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Easy Chocolate Zucchini Cake
Ingredients
For the cake:
- 1 cup plus 2 tablespoons (143 grams) all-purpose flour, measured correctly
- 1/2 cup (43 grams) unsweetened cocoa, measured correctly
- 1 cup (200 grams) light brown sugar
- 1 teaspoon salt
- 1 teaspoon baking soda
- 4 tablespoons (57 grams) unsalted butter, melted
- 1/4 cup fresh vegetable oil
- 1/2 cup (120 grams) full fat sour cream or plain whole milk yogurt, at room temperature
- 2 large eggs plus 1 egg yolk, at room temperature
- 2 teaspoons vanilla extract
- 1 cup (136 grams) shredded zucchini, from about 1 medium zucchini
- 1 cup (170 grams) semisweet chocolate chips
For the icing:
- 1/2 cup (63 grams) powdered sugar, sifted
- 1 tablespoon milk
Instructions
Make the cake:
- Preheat the oven to 350°F. Line an 8 by 8-inch metal baking pan* with parchment paper then spray with nonstick cooking spray.
- In a large bowl, whisk together the flour, cocoa, sugar, salt, and baking soda.
- In a small bowl, whisk together the melted butter, oil, sour cream, eggs, egg yolk, and vanilla extract.
- Make a well in the center of the dry ingredients and pour in the wet ingredients. Stir until a few streaks of flour remain. Squeeze out any additional moisture from the shredded zucchini before adding to the batter (see recipe post for tips on reducing excess moisture, which will create a gummy cake texture). Add in the chocolate chips. Stir until just barely combined.
- Pour the batter into the prepared pan and bake for 30 minutes or until a toothpick or cake tester comes out clean. If your cake sinks slightly in the middle, that's normal because it's so moist and rich!
- Let cool completely.
Make the frosting:
- In a medium bowl, stir together the sugar and milk with a fork until smooth and thick but pourable. Drizzle all over the cake. Let set before serving.
- Cake can be stored in an airtight container at room temperature for up to 4 days.
Recipe Notes
Photos by Ashley McLaughlin.
So delicious! Definitely needed an extra 10 mins or so but it was well worth it!
decided to actually measure all the ingredients for this recipe. the cake turned out absolutely delicious! it was def a crowd pleaser and my 5 yr old grandson, who helped me make it, had 3 pieces and licked his plate clean! excellent! thank you for this recipe. will def make it again in the near future.
Moist 😉 amazing chocolate cake ever !
Thank you so much for sharing.
have made it about….. hmmm 8 times now…
Excellent , moist and chocolaty . Does not need icing. I used whipped cream but you don’t need any topping
Hi can I make this into a double layer 6”
Inch cake with chocolate frosting ?
Hi Tricia! We haven’t tried that, so I can’t say for sure! Let us know if you give that a try 🙂
I’m a pretty awful cook but I followed this recipe exactly and it came out amazing. I don’t think it needs the frosting. Thank you!
Can I use a food processor instead of grating and then following the rest of the recipe to remove moisture?
Hi Erica! Yes, using the shredding attachment/insert in your food processor should work just fine. Let us know what you think of this cake once you’ve given it a try! 🙂
delicious fun recipe! Thank you for including weight measurements!!
A terrific recipe! I brought it as dessert to a dinner party and it was a big hit. It took longer than 30 minutes in the oven. Next time I will probably make it 375-degrees. Thank you for the best recipe for zucchini chocolate I have found.
Since I only had Dutch cocoa in my kitchen I swapped the 1 teaspoon baking soda for 1 teaspoon baking powder and 1/2 teaspoon baking soda. Also, I live in Canada so I combined our all purpose flour with our cake & pastry flour to equal the protein content of US all purpose flour. It was amazing! Cake was fluffy, did not fall in the middle and was delish!
Bomb. Super moist, almost has a chocolate lava type flavor.
I have an abundance of spaghetti squash which I have already baked and shredded. Any chance I could sub this for the zucchini? And, what are your thoughts on baking this in a bundt pan?
Hi Suzanne! We haven’t tested this cake using anything but zucchini, and I’m honestly not sure if the moisture content would be the same. I recommend instead checking out Tessa’s recipe for Spaghetti Squash Spaghetti here! We have also only tested this recipe using an 8×8-inch metal baking pan, which may hold a different capacity of batter. Check out this pan conversion guide for more info on that, and just know that changing pan sizes like this will also mean adjusting the bake time. I hope this helps, Suzanne! Let us know how it goes 🙂
Easy to make and absolutely delicious !! I will definitely be making this often .