Make an easy gluten-free chocolate Kit Kat cake with moist chocolate layers, homemade chocolate buttercream, wafer bars, and elegant chocolate curls.
Rich, festive, and overflowing with chocolate, this Easy Gluten-Free Chocolate Kit Kat Cake with Chocolate Buttercream Recipe makes an impressive centerpiece for birthdays, anniversaries, graduations, holidays, and other special celebrations.
Moist chocolate cake layers are covered with fluffy homemade chocolate buttercream, surrounded by gluten-free chocolate wafer bars, and topped with an elegant mixture of milk, dark, and white chocolate curls.
Choose from four chocolate cake variations, including a homemade flour blend, a gluten-free all-purpose flour version, a measure-for-measure flour option, or a convenient cake mix shortcut. Each variation produces two chocolate cake layers that pair beautifully with the dark cocoa buttercream and decorative chocolate border.
Because traditional Kit Kat bars are not necessarily gluten-free, select chocolate wafer bars that are specifically labeled gluten-free. Check the labels on the pudding mix, chocolate chips, cocoa powder, decorations, and other packaged ingredients as well. With careful ingredient selection and preparation, this spectacular cake can become a memorable dessert for anyone who loves layers of chocolate.
Ingredients
Choose One Cake Batter Option
Option 1: Ultimate Homemade Gluten-Free Chocolate Cake
1/4 cup gluten-free oat flour
1/2 cup cornstarch
1/2 cup white rice flour
1 cup glutinous rice flour
1/2 cup tapioca flour
2 1/2 teaspoons baking powder
1/2 teaspoon baking soda
1/2 teaspoon xanthan gum
1/2 teaspoon kosher salt
2/3 cup unsweetened Black Dutch-process cocoa powder
1 1/3 cups granulated sugar
2 sticks unsalted butter, softened and diced, or 1 cup neutral oil
4 large eggs
1/2 cup neutral oil, only if using butter
1 cup buttermilk
3 tablespoons pure vanilla extract
8 ounces sour cream
3 ounces instant chocolate pudding mix
1/2 package mini chocolate chips
Option 2: Easy Gluten-Free Chocolate Cake
1 1/2 cups granulated sugar
1 1/2 cups gluten-free all-purpose flour
1 cup Black Dutch-process cocoa powder
2 1/2 teaspoons baking powder
1 teaspoon salt
1 teaspoon xanthan gum
2/3 cup neutral oil
4 large eggs
1 1/3 cups water
2 teaspoons pure vanilla extract
Option 3: Measure-for-Measure Chocolate Cake
2 1/4 cups measure-for-measure gluten-free flour
2 cups granulated sugar
3/4 cup Black Dutch-process cocoa powder
2 teaspoons baking powder
1/2 teaspoon baking soda
1 teaspoon salt
4 large eggs, at room temperature
3/4 cup neutral oil
2 teaspoons pure vanilla extract
1 1/4 cups water
Option 4: Gluten-Free Cake Mix Shortcut
1 box gluten-free chocolate cake mix
8 ounces sour cream
3 ounces instant chocolate pudding mix
1/2 large package chocolate chips
1/2 cup neutral oil
1 cup water
4 large eggs
For the Chocolate Buttercream
2 cups unsalted butter, softened
5 1/2 cups powdered sugar
1 cup Black Dutch-process cocoa powder
1/4 teaspoon kosher salt
2 teaspoons pure vanilla extract
4 to 6 tablespoons heavy cream
For the Chocolate Decorations
18 to 20 gluten-free chocolate wafer bars
2 to 3 cups milk, dark, and white chocolate curls
Additional chocolate shavings, if desired
Directions
Step 1: Prepare the Oven and Cake Pans
Preheat the oven to 350°F. Grease two 8-inch or 9-inch round cake pans. Line the bottoms with parchment paper and set the prepared pans aside.
Step 2: Make Option 1, if Using
Whisk the gluten-free oat flour, cornstarch, white rice flour, glutinous rice flour, tapioca flour, baking powder, baking soda, xanthan gum, kosher salt, cocoa powder, and granulated sugar together in a large bowl.
In a separate large bowl, beat the softened butter, eggs, 1/2 cup neutral oil, buttermilk, vanilla extract, sour cream, and chocolate pudding mix until smooth. If using 1 cup neutral oil instead of butter, omit the additional 1/2 cup of oil.
Gradually add the dry ingredients to the wet mixture and mix just until fully incorporated. Fold in the mini chocolate chips.
Step 3: Make Option 2, if Using
Whisk the granulated sugar, gluten-free all-purpose flour, cocoa powder, baking powder, salt, and xanthan gum together in a large bowl.
Add the oil, eggs, water, and vanilla extract. Beat until the batter is smooth and evenly combined.
Step 4: Make Option 3, if Using
Whisk the measure-for-measure gluten-free flour, granulated sugar, cocoa powder, baking powder, baking soda, and salt together in a large bowl.
Add the eggs, oil, vanilla extract, and water. Mix until the batter is smooth and no pockets of dry ingredients remain.
Step 5: Make Option 4, if Using
Place the gluten-free chocolate cake mix, sour cream, chocolate pudding mix, chocolate chips, oil, water, and eggs in a large mixing bowl.
Beat for about 2 minutes, or until the batter is smooth and evenly combined.
Scrape the bottom and sides of the bowl as necessary.
Step 6: Bake the Cake Layers
Divide your selected cake batter evenly between the prepared pans. Smooth the tops with a spatula.
Bake for 30 to 40 minutes, or until a toothpick inserted into the center of each cake comes out clean or with only a few moist crumbs attached.
Let the cakes cool in their pans for 15 minutes. Carefully turn the layers out onto wire racks, remove the parchment paper, and allow the cakes to cool completely before frosting.
Step 7: Prepare the Chocolate Buttercream
Place the softened butter in the bowl of a stand mixer fitted with the paddle attachment or in a large bowl suitable for a hand mixer. Beat for 3 to 4 minutes, or until very creamy and fluffy.
Gradually add the powdered sugar and Black Dutch-process cocoa powder, mixing on low speed until incorporated. Add the vanilla extract and kosher salt.
Beat in the heavy cream 1 tablespoon at a time until the buttercream reaches a smooth, creamy, and easily spreadable consistency. Increase the speed and continue beating for another 3 to 5 minutes, or until the frosting is light and fluffy.
Step 8: Fill and Crumb-Coat the Cake
Place one completely cooled cake layer on a serving plate or cake stand. Spread approximately 1 1/2 cups of chocolate buttercream evenly over the top.
Position the second cake layer over the buttercream. Spread a thin crumb coat of frosting over the top and sides of the entire cake.
Refrigerate the crumb-coated cake for about 20 minutes, or until the buttercream feels firm.
Step 9: Frost the Cake
Cover the chilled cake with the remaining chocolate buttercream. Smooth the top and sides with an offset spatula or cake scraper.
Make sure there is enough buttercream on the sides to hold the chocolate wafer bars securely in place.
Step 10: Add the Gluten-Free Chocolate Wafer Bar Border
Starting at one point on the cake, gently press the gluten-free chocolate wafer bars vertically into the buttercream. Continue arranging the bars side by side until the cake is completely surrounded.
Trim the bars if necessary to create an even border around the cake. Avoid pressing so firmly that the bars break or push deeply into the cake.
Step 11: Decorate with Chocolate Curls
Generously pile the milk, dark, and white chocolate curls over the top of the cake.
Arrange the different colors of chocolate throughout the topping to create a decorative bakery-style finish.
Scatter additional chocolate curls or shavings around the base of the cake, if desired.
Step 12: Chill and Serve
Refrigerate the decorated cake for 20 to 30 minutes to allow the buttercream to firm slightly and help secure the chocolate wafer bar border.
Remove the cake from the refrigerator approximately 20 minutes before serving for the best flavor and texture. Cut it into slices using a sharp knife and serve.
Notes
Black Dutch-process cocoa powder gives the cake and buttercream a deep chocolate flavor and dramatic dark color.
The Ultimate Homemade Gluten-Free Chocolate Cake option produces the richest and moistest variation, making it especially suitable for celebrations.
When preparing Option 1 with butter, include the additional 1/2 cup of neutral oil.
When replacing the butter with 1 cup of neutral oil, omit that additional 1/2 cup.
Despite its name, glutinous rice flour does not contain gluten. It is made from sticky rice. Choose a package labeled gluten-free when preparing the cake for someone with celiac disease or gluten sensitivity.
Traditional Kit Kat bars may contain gluten and should not automatically be considered safe for this recipe. Use chocolate wafer bars specifically labeled gluten-free, and verify the package each time because ingredients and manufacturing practices can change.
Check the labels on the oat flour, all-purpose flour, measure-for-measure flour, cake mix, pudding mix, cocoa powder, chocolate chips, chocolate wafer bars, chocolate curls, and other packaged ingredients. Prevent cross-contact by using clean bowls, utensils, pans, work surfaces, and decorating equipment.
Chocolate curls are easiest to make with room-temperature chocolate and a vegetable peeler. Refrigerate the curls briefly if they become too soft to handle.
For clean slices, warm a sharp knife under hot water, wipe it completely dry, and clean it between cuts.
Store leftover cake covered in the refrigerator for up to 5 days. Let individual slices stand briefly at room temperature before serving so the buttercream can soften.
Unfrosted cake layers may be frozen for up to 3 months. Wrap the completely cooled layers securely before freezing, then thaw them overnight in the refrigerator before assembling and decorating the cake.
