Impossibly easy and moist gluten free chocolate zucchini cake recipe mixes together in one bowl, versatile as a sheet or layer cake, and has a rich velvety frosting to make this one of best zucchini desserts ever. If you want to wow guests with an epically fabulous GF zucchini cake recipe, then this is the one to make.

a slice of gluten free zucchini cake facing up in a baking pan

Want to Save This Recipe?

Enter your email below & we'll send it straight to your inbox. Plus you’ll get affordable and easy gluten-free recipes delivered each week!

Epically Moist Chocolate Gluten-Free Zucchini Cake

Since summer means either an abundance of zucchini in the garden or farmer’s market, I am no stranger to making my fair share of easy gluten free recipes using zucchini. This chocolate zucchini cake has been deemed as one of the best GF cake options because, when serving, I’m the only one who knows it’s gluten-free!

What makes it so special? Well, it’s right up there with gooey chocolate chip gluten-free zucchini cookies as one of my most requested summer desserts. The texture is so spot on of a traditional chocolate cake, guests have a hard time believing it’s made with grated zucchini.

Using zucchini in gluten-free cakes is kind of like a magic potion. Gluten-free flour has a harder time absorbing moisture, which is why they have the tendency to be dry and crumbly. When adding unsweetened cocoa powder into the mix too, you really have to compensate for a potentially dry crumb.

How do we fix that? When testing this recipe for homemade chocolate zucchini cake I still wanted to maintain a light, fluffy texture. Instead of adding more oil, swapping out some of it with sour cream did the trick. It adds moisture, but also suspends lighter in the cake, so it doesn’t weigh down the crumb.

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! And even better served cold the next day. Doubled the recipe and served it to my large extended family. The compliments came rolling in and nobody could believe it when I told them it was GF! And then another gasp when I revealed it had zucchini!

—Kimberly

Ingredient Tid Bits

Just like my homemade gluten-free chocolate cake recipe, the ingredients are simple and readily available in many home cooks’ kitchens. It requires three cups of grated zucchini, which equals about 2 medium zucchini.

  • Gluten-free flour – My preferred brand of gluten free all-purpose flour is Cup4Cup, but King Arthur Measure-for-Measure also performs well. Cup4Cup has cornstarch in the blend, which will make the cake batter quite thick. Once baked, though, the texture will be fine.
  • Eggs – The recipe requires four eggs, which is more than typical cake recipes. This helps with lift and structure. Since zucchini recipes can be dense due to extra moisture, adding an additional egg or two offsets this.
  • Oil – Similar to double chocolate chip gluten free zucchini bread, oil works better than butter in zucchini recipes. It requires no creaming or mixing, and the neutral flavor helps the chocolate shine through.
  • Sour cream – To reduce the amount of oil needed in the cake, I added 1/3 cup sour cream. If you need a dairy free gluten free recipe, simply substitute 1/3 cup unsweetened applesauce or use 1/3 cup more oil.
  • Unsweetened Cocoa Powder – If you love a darker chocolate flavor use dutch-processed cocoa powder for the cake and chocolate frosting. With the chocolate chips added to the cake batter, though, I don’t think you miss out on any chocolatey flavor!

Let’s Make This Together!

(Note: This is a step-by-step tutorial with pictures. For more specific instructions, along with ingredient amounts, see the recipe card at the bottom of the post.)

Whisk the dry ingredients

First whisk together the gluten-free flour, sugar, cocoa, baking soda, baking powder, and salt. If using a mixer, mix on low speed until combined.

gluten free flour, sugar, cocoa, and other dry ingredients being whisked together in a large glass bowl.

Beat in the wet ingredients

Add the eggs, oil, sour cream, and vanilla. Beat it together and at this point the batter will be very thick. If you have made my famous gluten-free zucchini brownies with peanut butter, it’s kind of the same way. You will doubt it will work, but zucchini adds a lot of moisture. As it bakes, water releases and you’ll have an absolutely perfect gluten-free zucchini cake crumb!

eggs and oil being added to the dry ingredients.

Fold in zucchini and bake

Fold in the grated zucchini and mini chocolate chips until evenly distributed. I like using miniature baking chips because they don’t sink to the bottom of the cake, staying evenly dispersed throughout.

Spread into a 9X13-inch baking pan and bake for 50-60 minutes, or until the middle is set and a toothpick comes out clean. Cool completely before frosting.

grated zucchini and mini chocolate chips added to the cake batter.

Don’t Miss Out On This Magic Chocolate Frosting!

I love, love, love this simple chocolate frosting on chocolate zucchini cake because it doesn’t use as much butter as a buttercream, meaning it’s a lot lighter tasting. Plus, adding a bit of sour cream makes it smooth and creamy, while adding a hint of tanginess.

However, one of the many reasons I love this sheet cake is how versatile it is for changing up flavors. Love peanut butter and chocolate paired together? This gooey peanut butter frosting is to die for.

A traditional uber fluffy vanilla buttercream, cream cheese frosting, or airy chocolate whipped cream frosting also works well. Choose whatever floats your boat!

    overhead shot of chocolate zucchini cake with chocolate frosting

    Bonus Baking Tips and Suggestions

    Larger zucchini contains more moisture, so you may want to squeeze some of the moisture out of the grated zucchini using paper towels before adding. If it is a very large zucchini, the seeds may also be scraped out before grating. However, if you are using small or medium zucchini, do not squeeze it out before adding or you will have a dry cake!

    If you’d rather do a layer cake, the batter can be divided between two 9-inch cake pans. Just be sure it’s sides are at least 2 inches high so it has room to rise. The baking time will be a lot shorter, about 25-30 minutes.

    You can also make more of a snack cake size. Halve all the ingredients and bake in a 8-inch square baking pan. The baking time will also decrease for that as well. Check around 25-30 minutes.

    a slice of chocolate cake on a wood plate with a bite taken out

    Save this recipe to your pinterest board!

    Pin Now, Bake Later!

    Let’s be friends on Pinterest! I’m always sharing great recipes!

    Did you make this recipe? I love hearing from you! Leave a star rating and comment below the recipe card. It helps others when searching for recipes and I appreciate feedback from our community. You will always hear back from me! -Melissa

    a slice of gluten free zucchini cake facing up in a baking pan
    4.78 stars (22 ratings)

    Moist & Fluffy Gluten Free Chocolate Zucchini Cake

    Melissa Erdelac of MamaGourmand headshot in patterned dress.Melissa Erdelac
    Yield: 24
    Prep Time: 20 minutes
    Cook Time: 50 minutes
    Total Time: 2 hours 10 minutes
    Impossibly easy and moist gluten free chocolate zucchini cake recipe mixes together in one bowl, versatile as a sheet or layer cake, and has a rich velvety frosting to make this one of best zucchini desserts ever. If you want to wow guests with an epically fabulous GF zucchini cake recipe, then this is the one to make.
    Print Pin Rate Remove Ads

    Ingredients
     

    Chocolate Frosting

    Equipment

    Instructions
     

    • Preheat the oven to 350°F. Grease a 9X13 inch pan with nonstick cooking spray and set aside. See recipe notes for using 9-inch layer cake pans.
    • In a large bowl whisk together the dry ingredients – flour, sugar, cocoa, baking soda, baking powder, and salt. If using a mixer, mix on low speed until combined.
      2 cups gluten free all purpose flour, 2 cups granulated sugar, ¾ cup unsweetened cocoa powder, 2 teaspoons baking soda, ½ teaspoon baking powder, ½ teaspoon salt
    • Add the eggs, oil, sour cream, and vanilla. Mix well, using a mixer on medium speed. The batter will be very thick.
      4 large eggs, 1 cup oil, ⅓ cup sour cream, 2 teaspoons vanilla extract
    • Fold in the grated zucchini and mini chocolate chips until evenly distributed. Pour into the prepared baking pan.
      3 cups grated zucchini, 1 cup (optional) mini chocolate chips
    • Bake for 50-60 minutes, rotating pan halfway through. Use a toothpick inserted in the middle to test if the cake is done. Cool completely before frosting.

    Chocolate Frosting

    • In a large bowl beat together the softened butter, 2 cups powdered sugar, cocoa powder, sour cream, and salt until the powdered sugar is mixed in.
      5 tablespoons unsalted butter , 3 cups powdered sugar, ⅓ cup unsweetened cocoa powder, 2 tablespoons sour cream, ¼ teaspoon salt
    • Add the milk and additional 1 cup powdered sugar. Beat on high speed for 1-2 minutes, or until well combined and fluffy. Spread on cooled cake.
      3-4 tablespoons milk

    Notes

    Layer cake directions
    Pour into two 9-inch cake pans, but they need to be at least 2-inches high. The cake rises pretty high and you don’t want to make a mess in your oven!
    The cake layers will have a much shorter baking time, about 25-30 minutes, rotating halfway through. Insert a toothpick in the middle to make sure it is cooked through.
    Dairy-Free Adaptations
    Omit the chocolate chips or use dairy-free chocolate chips instead. For the frosting, replace the butter with plant-based butter sticks, such as Earth Balance, but omit the salt in the recipe. Forgo the sour cream and add an additional tablespoon of dairy free milk.
    Storing / Freezing
    After cooling and frosting, store covered, at room temperature, up to 3 days. Do not refrigerate the cake because it will dry it out.
    To freeze, place the cake in the freezer until the frosting is solid. Then, wrap securely in plastic wrap and finish with a layer of foil. Leftover slices may also be frozen, individually wrapped in plastic wrap and places in a ziplock freezer bag.
    Calories: 289kcal, Carbohydrates: 42g, Protein: 3g, Fat: 14g, Saturated Fat: 3g, Polyunsaturated Fat: 3g, Monounsaturated Fat: 7g, Trans Fat: 1g, Cholesterol: 35mg, Sodium: 153mg, Potassium: 133mg, Fiber: 2g, Sugar: 32g, Vitamin A: 162IU, Vitamin C: 3mg, Calcium: 32mg, Iron: 1mg
    Did you make this recipe?Please leave a star rating and review below. It helps others when searching for recipes and I LOVE feedback!