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This Chocolate Zucchini Cake with Chocolate Buttercream is exactly what every chocolate cake should be: rich and decadent! It's an easy sheet cake recipe that ends up incredibly tender and sweet. A great chocolate dessert for everyone to enjoy!
This is the ultimate chocolate cake! It is sweet but with a very rich chocolate flavor. If you are a chocolate lover, this cake is for you! Yea the title has zucchini it and yea the cake has zucchini it, but honestly you can't even tell! The zucchini blends with the chocolate and adds so much moisture making this cake irresistible. Any chocolate lover, zucchini fan or not, is going to love this cake!
This post was originally posted on 5/02/2020 and updated on 9/29/2021.
Ingredients for Chocolate Zucchini Cake with Chocolate Buttercream
- Canola Oil
- Pure Vanilla Extract
- Whole Wheat Flour
- Unbleached All Purpose Flour
- Unsweetened Baking Cocoa
- Baking Powder
- Baking Soda
- Shredded Zucchini
- Salted Butter
- Powdered Sugar
- Canola Oil: I prefer canola oil for baking, however another neutral oil can be substituted. Avocado, olive, or vegetable oil will work.
- Whole Wheat Flour/All Purpose Flour: Either of the flours can be used in this cake. I prefer a blend of both, but you can use all whole wheat or all purpose.
- Buttermilk: If you don't have buttermilk on hand you can make your own, or you can use milk you would normally drink. Half and half can also be used.
How to Make Homemade Buttermilk:
It's really simple to make your own buttermilk. If you have milk and lemon juice or vinegar you can skip the trip to the store. Combine 1 tablespoon of lemon juice or white vinegar per 1 cup of milk. Let it sit for at least 5 minutes then use for this cake and other favorite recipes.
How to Make Chocolate Zucchini Cake
- In a stand mixer or with hand beaters, beat together the sugar and eggs until they are pale yellow and fluffy.
- Add the canola oil and vanilla extract and beat well.
- Next, add the whole wheat flour, all purpose flour, baking powder, baking soda, and salt. Mix on low just until combined.
- Beat in buttermilk on low until fully incorporated.
- Lastly, fold in the shredded zucchini, scraping the sides of the bowls and ensuring everything is fully incorporated.
- Pour the cake batter into a greased 9x13 cake pan.
- Bake the cake in a 350°F preheated oven for 35-45 minutes and until a toothpick inserted in the center comes out clean.
- Let the cake cool completely before frosting.
How to Make Chocolate Buttercream Frosting
- Beat the softened butter until creamy.
- Add the cocoa powder, vanilla extract and half of the powdered sugar. Beat until fully incorporated.
- Now, add the remaining powdered sugar and milk. Beat on low until the sugar is all mixed in, being sure to scrape the sides of the bowl.
- Bump up the speed to medium and beat the frosting for 2-3 minutes until light and fluffy.
- Spread the frosting over the cooled cake.
Do I have to peel the zucchini for Chocolate Zucchini Cake?
Nope! No need to spend extra time peeling the zucchini. If you would rather peel it you can, but it's an unnecessary step. The skin on zucchini is thin enough that it becomes really tender when baked in this yummy cake.
What is the best way to shred zucchini?
I shred zucchini two different ways. If I only need a cup or so of shredded zucchini, I’ll grab a small zucchini and shred it with a box grater. However, I often get large zucchinis (because they grow so fast sometimes!) so I’ll get out the food processor and shred a bunch of zucchini at once. I like to do this because then I can make a few extra batches of breads and muffins and freeze them for the kids so they are available for their lunches and snacks. The extra shredded zucchini also freezes well, so I can have some available all year long.
How do I drain the zucchini?
Place a paper towel in a strainer and put the shredded zucchini on top. That's all you do. Some recipes call for squeezing the zucchini, in this recipe you do NOT want to do that. The extra moisture from the zucchini is what makes this cake so great! I use frozen shredded zucchini often, and I use the same method with both freshly grated and thawed zucchini.
How to Make a Layered Chocolate Zucchini Cake
Cake: Follow all the directions and pour the batter into 2 greased and lined 9 inch round pans. Bake for 20-25 minutes or until a toothpick inserted in the center comes out clean. Let the cakes cool for 15 minutes, then turn them out of the pans and cool completely.
Frosting: Double the frosting ingredients and proceed with the recipe instructions. Doubling it will provide enough frosting for the filling and outer edges of the cake.
Assembling: Once the cakes are cool, add a tablespoon or so of frosting to the bottom of a cake plate. Place one cake on top of the frosting then add about a ½ inch thick of frosting on top. Now place the other cake on top of the frosting. Finish the cake off by frosting the top and sides of the cake. Let the cake rest for about 15-20 minutes before slicing.
Other Delicious Zucchini Recipes:
- Chocolate Chip Zucchini Bread
- Pumpkin Zucchini Muffins
- Air Fryer Zucchini Fries
- Cinnamon Swirl Zucchini Bread
- Turkey & Zucchini Meatballs
- Zucchini Frittata
- Classic Zucchini Bread
- Cheesy Zucchini Biscuits
Chocolate Zucchini Cake
For the Cake
For the Cake
- Preheat oven to 350°F and grease a 9x13 cake pan or baking dish.
- In a stand mixer or with hand beaters, beat together the sugar and eggs until pale yellow and fluffy.
- Add the canola oil and vanilla extract, beat well.
- Add the whole wheat flour, cocoa powder, baking powder, baking soda and salt. Mix on low just until combined.
- Beat the buttermilk in on low until fully incorporated.
- Fold in shredded zucchini, scraping the sides of the bowl and ensuring everything is completely combined.
- Pour the batter into prepared cake pan and bake for 35-45 minutes until toothpick inserted in the center comes out clean.
- Let cake cool completely before frosting.
For the Frosting
- Beat softened butter until fluffy.
- Add the cocoa powder, vanilla extract and half of the powdered sugar. Beat until everything is incorporated.
- Add the remaining powdered sugar and milk. Beat on low just until everything is mixed together being sure to scrape the sides of the bowl.
- Increase the speed to medium and beat for 2-3 minutes until light and fluffy.
- Frost cooled cake and serve.