This post may contain affiliate links. Please read our disclosure policy.
Soft and moist chocolate zucchini cake is deliciously sweet. You’d never guess it’s filled with grated zucchini!
Zucchini is a surprisingly delicious addition to a classic Chocolate Cake recipe, and it adds the perfect amount of moisture. This chocolate zucchini cake is just as moist as our Sour Cream Chocolate Cake!
chocolate Cake + Zucchini
Now that summer is coming to a close, zucchini is abundant and recipes have been popping up everywhere. Instead of using it in my favorite bread, I decided to grate some up and use it in this incredible chocolate zucchini cake. It’s the BEST!
No one will ever guess that there’s zucchini in this cake! It practically disappears into thin air when baked.
Instead of using a full-size cookie sheet to bake the batter in, I opted for a 9×13-inch pan. That way it comes out nice and thick. If you love chocolate cake, you will love this!
How to make chocolate Zucchini Cake
This chocolate zucchini cake recipe is simple and packed with chocolate flavor!
PREP. Preheat oven to 350°F. Butter a 9×13-inch baking pan.
BATTER. In a large bowl, whisk together the flour, cocoa powder, baking soda, and salt. Create a well or nest in the center of the dry ingredients and pour in the melted butter, buttermilk, vanilla extract, and eggs.
Using a rubber spatula or wooden spoon stir for 10 seconds, then fold in the grated zucchini. Continue mixing until no flour pockets remain.
BAKE. Place into prepared baking pan. Bake for 25-28 minutes. Remove from the oven and allow to cool.
FROSTING. Meanwhile, to make the frosting, in a medium saucepan set over low heat, melt the butter, then add the milk and sifted cocoa powder. Stir to combine, then remove from the heat and add the vanilla extract and the sifted powdered sugar.
Spread over the slightly warm cake. Allow to cool and set for 30 minutes before slicing and serving.
Recipe Tips
Make the best chocolate zucchini cake with these simple tips!
Zucchini. No need to peel the zucchini before shredding it. Just wash and dry it. Shred the zucchini with the smaller grate. The finer shredded zucchini will have a less noticeable texture in the cake.
Batter. Don’t forget to sift the cocoa and sugar as they have a tendency to clump. To avoid overmixing don’t use an electric mixer. Mixing this cake by hand will produce a softer moist crumb.
Buttermilk. If you don’t have buttermilk on hand you can make your own using milk and lemon juice.
Additions. You can add chocolate chips or chopped nuts directly to the cake batter or sprinkle it on top of the frosting.
Easy clean up. Lining your cake pan with parchment paper can help keep the cake from sticking for easy removal.
Baking pans. Easily cook this up in different pans. Since different ovens can cook a little differently start checking 5 minutes before the suggested end time. Insert a toothpick if it comes out clean, then it’s done.
- Cupcakes: 350°F bake for 18-22 minutes
- Two 9” round pans: 350°F bake for 25-32 minutes
- Sheet cake pan: 350°F for 28-30 minutes
- Bundt cake pan: 350°F for 50-55 minutes
Storing Info
STORE. Always store a cool cake. Warm cakes will continue to steam and the extra moisture can cause the cake to get soggy.
- Counter: Cover leftover chocolate cake with zucchini and store it at room temperature for 3-4 days.
- Fridge: Cover and store in the refrigerator for 5-7 days.
- Freezer: Wrap the cake whole, or sliced, with plastic wrap then again with aluminum foil. If it has frosting flash freeze first. Label and freeze for 2-3 months. Thaw before serving.
Recipe FAQ
Absolutely! Freezing your vegetables is a great way to preserve them to use later. Shredded zucchini can last in the freezer for 3-4 months. Be sure to squeeze the liquid out before freezing it and after it has thawed.
I recommend using natural cocoa powder, but in a pinch, you can use the dutch process. Replace the natural cocoa with an equal amount of dutch process AND replace the baking soda with 3 teaspoons of baking powder. The baking powder will help replace the acid that is in natural cocoa but not dutch processed cocoa which is needed to help the cake rise.
After the zucchini has been shredded, place it in a nut milk bag or kitchen towel and wring it out. A good quality paper towel can also be used to absorb excess moisture.
For More Baked Zucchini Recipes, Try:
- Zucchini Bread
- Lemon Zucchini Bread
- Zucchini Cake with Cream Cheese Frosting
- Zucchini Muffins
- Lemon Zucchini Muffins
Zucchini Chocolate Cake Recipe
Ingredients
Cake
- 2 cups all-purpose flour
- 1/2 cup Hershey's unsweetened cocoa powder
- 2 teaspoons baking soda
- 1 teaspoon salt
- 1 3/4 cup sugar
- 1 cup butter melted
- 1 teaspoon vanilla extract
- 3 large eggs lightly beaten
- 3/4 cup buttermilk
- 2 cups zucchini grated and squeezed dry
Frosting
- 3/4 cup butter
- 1/3 cup milk or cream
- 1/4 cup cocoa powder sifted
- 1 teaspoon vanilla extract
- 3 1/2 cups powdered sugar sifted
Instructions
- Preheat oven to 350 °F and prep a 9×13 inch baking dish with cooking spray or butter.
- In a large mixing bowl, whisk together the flour, cocoa powder, baking soda, salt and sugar. Create a well or nest in the center of the dry ingredients and pour in the melted butter, buttermilk, vanilla extract, and eggs. Using a spatula or wooden spoon stir for 10 seconds, then fold in the grated zucchini. Continue mixing until no flour pockets remain.
- Place into a buttered (or sprayed) 9×13-inch baking pan. Place in the oven and bake at 350°F for 25-28 minutes. Remove from the oven and allow to cool.
- Meanwhile, to make the frosting, in a medium saucepan set over low heat, melt the butter, then add the milk and sifted cocoa powder. Stir to combine, then remove from the heat and add the vanilla extract and the sifted powdered sugar. Spread over the slightly warm cake. Allow to cool and set for 30 minutes before slicing and serving.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
—————————————————————–
I LOVE, and I mean LOVE Zucchini recipes – especially sweet ones! Can’t wait to try this, Natalie! Thank you! For more great recipes be sure to check out Life Made Simple.
Can the eggs be substituted in this recipe?
I have never tried using an egg substitute in this recipe. If you do, you’ll have to let us know how it turns out.
Sugar is not included in recipe instructions, so I forgot to add! 🤦♀️
Thanks for pointing that out. We’ll get the instructions updated.
This chocolate zucchini cake is the best way to use up leftover summer zucchini! It was so easy to make and tasted amazing! Thank you!!
Talk about delicious and what an awesome way to use up all of that zucchini I had on my counter!
Oh man, was this ever yummy!
Question: the cake ingredients call for unsweetened cocoa while the frosting ingredients call for cocoa powder. Are these two cocoa powders the same? if not what is the difference?
Sorry, yes, they are the same 🙂