Impossibly easy and incredibly moist, this gluten-free chocolate zucchini cake comes together in one bowl and works perfectly as a sheet cake or a layered cake. Finished with a velvety chocolate frosting, it’s one of the best zucchini desserts to serve when you want something nostalgic, rich, and unexpectedly light. Guests will be amazed it’s gluten-free—and that it contains zucchini.
Moist Chocolate Gluten-Free Zucchini Cake Recipe
Summer often brings a bounty of zucchini from gardens or farmers’ markets, and this chocolate zucchini cake is an excellent way to use it. The cake texture is so close to a classic chocolate cake that most people won’t realize it’s gluten-free. The grated zucchini adds moisture and a tender crumb without a vegetal flavor, while the cocoa and optional chocolate chips deliver full chocolate satisfaction.
Gluten-free flours can struggle to retain moisture, so baked goods made with them often turn out dry or crumbly. Adding cocoa powder makes that challenge bigger because it can dry the batter further. To combat this and keep the cake light, this recipe replaces some of the oil with sour cream. Sour cream adds moisture and helps suspend air in the batter so the finished cake remains fluffy rather than dense.
“The best chocolate zucchini cake ever. My husband says it’s pretty hard to beat that cake. Can’t even believe it’s gluten free. Wow!”
—Anna
“This was incredible! Even better cold the next day. I doubled the recipe for a large family gathering and everyone raved about it. No one believed it was gluten free—and then they were shocked it had zucchini!”
—Kimberly
Ingredient Notes
The ingredient list is straightforward and uses pantry staples. You’ll need about 3 cups grated zucchini, which equals roughly 2 medium zucchini. Below are a few helpful notes about the main ingredients:
- Gluten-free flour – Use a good-quality gluten-free all-purpose blend. Different blends vary in texture; some contain starches that make the batter thicker but the baked cake will still be tender.
- Eggs – This recipe uses four eggs to provide structure and lift. Extra eggs help offset the moisture zucchini adds so the cake rises properly.
- Oil – A neutral oil (vegetable or canola) keeps the cake tender and lets the chocolate flavor shine. Oil also simplifies mixing since there’s no need to cream butter and sugar.
- Sour cream – Replacing some oil with sour cream improves moisture and texture. For a dairy-free version, see the notes in the recipe card.
- Unsweetened cocoa powder – Dutch-processed cocoa will give a darker, milder chocolate flavor; natural cocoa also works. Mini chocolate chips are optional and are less likely to sink in the batter than larger chips.
Let’s Make This Together
(Note: this is a step-by-step overview. For exact ingredient amounts and full directions see the recipe card below.)
Whisk the dry ingredients
Combine the gluten-free all-purpose flour, granulated sugar, unsweetened cocoa powder, baking soda, baking powder, and salt in a large bowl. If you prefer, use a stand or hand mixer on low speed to blend evenly.
Beat in the wet ingredients
Add the eggs, oil, sour cream, and vanilla and beat until incorporated. The batter will be thick; that’s normal. Zucchini releases moisture as the cake bakes, creating a perfect crumb even if the batter looks dense at first.
Fold in zucchini and bake
Gently fold in the grated zucchini and mini chocolate chips until evenly distributed. Mini chips are preferred because they stay suspended throughout the cake.
Spread the batter into a greased 9×13-inch pan and bake at 350°F for 50–60 minutes, rotating halfway. The cake is done when a toothpick inserted in the center comes out clean. Cool completely before frosting.
Chocolate Frosting
This frosting is rich but lighter-tasting than a traditional buttercream because it uses less butter and includes sour cream for a smooth, creamy texture with a pleasant tang. It’s easy to make and spreads beautifully on the cooled cake.
If you prefer different flavors, this cake also pairs well with peanut butter glaze, vanilla buttercream, cream cheese frosting, or a chocolate whipped cream. Choose the topping that best suits your taste and occasion.
Bonus Zucchini Baking Tip
Larger zucchini tend to have more water. If your zucchini is very large, scrape out the seeds before grating and gently squeeze some excess moisture from the grated zucchini with paper towels. If you’re using small or medium zucchini, do not squeeze them dry—those contribute valuable moisture and keep the cake tender.
Did you make this recipe? I love hearing how it turned out! Leave a rating and comment below the recipe card to help others and to share your tips. —Melissa
Moist & Fluffy Gluten Free Chocolate Zucchini Cake
Ingredients
- 2 cups gluten-free all-purpose flour
- 2 cups granulated sugar
- 3/4 cup unsweetened cocoa powder
- 2 teaspoons baking soda
- 1/2 teaspoon baking powder
- 1/2 teaspoon salt
- 4 large eggs
- 1 cup oil (vegetable or canola)
- 1/3 cup sour cream
- 2 teaspoons vanilla extract
- 3 cups grated zucchini (about 2 medium)
- 1 cup mini chocolate chips (optional)
Chocolate Frosting
- 5 tablespoons unsalted butter, softened
- 3 cups powdered sugar (divided)
- 1/3 cup unsweetened cocoa powder
- 2 tablespoons sour cream
- 1/4 teaspoon salt
- 3–4 tablespoons milk
Instructions
- Preheat the oven to 350°F. Grease a 9×13-inch pan and set aside. (For layer cakes, see notes below.)
- In a large bowl whisk together the flour, sugar, cocoa, baking soda, baking powder, and salt.
- Add the eggs, oil, sour cream, and vanilla. Mix on medium until well combined; the batter will be thick.
- Fold in the grated zucchini and mini chocolate chips. Pour into the prepared pan and smooth the top.
- Bake 50–60 minutes, rotating the pan halfway through. Test with a toothpick; it should come out clean. Cool completely before frosting.
Frosting
- Beat the softened butter with 2 cups powdered sugar, cocoa powder, sour cream, and salt until combined.
- Add milk and the remaining powdered sugar and beat on high for 1–2 minutes until light and fluffy. Spread on the cooled cake.
Notes
Layer cake directions
Divide batter between two 9-inch cake pans that are at least 2 inches deep. Bake 25–30 minutes, rotating once. Use a toothpick to check doneness.
Dairy-free adaptations
Use dairy-free chocolate chips or omit them. For frosting, swap butter for a plant-based stick and skip added salt, replace sour cream with an additional tablespoon of dairy-free milk.
Storage and freezing
Store covered at room temperature up to 3 days. Do not refrigerate or the cake may dry out. To freeze, chill until the frosting firms, then wrap tightly in plastic wrap and foil. Individual slices can be wrapped and placed in a freezer bag.
Calories: 289 kcal • Carbs: 42 g • Protein: 3 g • Fat: 14 g • Sugar: 32 g