Chocolate Layer Cake with Peanut Butter Buttercream Frosting

This isn’t your ordinary chocolate cake. It’s dense, just sweet enough, and deeply satisfying—like a cross between a brownie and a peanut butter cup.

Why you’ll love this chocolate peanut butter cake

I made this chocolate layer cake with peanut butter buttercream for my friend Juli Roth’s baby shower in Denver. When I asked what she wanted, she said “chocolate and peanut butter,” so I set out to build a dense, almost brownie-like cake that pairs perfectly with a light, creamy peanut butter frosting.

After testing several recipes and experimenting with gluten-free swaps, I developed a version that’s simple in technique but yields a rich, moist cake. It takes a little care—especially with the double boiler step—but the result is worth it. The cake is make-ahead friendly and the frosting spreads beautifully for a clean finish.

Ingredients

Everything you need to make this gluten-free-friendly chocolate cake with peanut butter buttercream:

For the cake

• 4 cups all-purpose or gluten-free flour
• 4 cups white sugar
• 1 cup cocoa powder
• 2 cups chocolate chips
• 4 large eggs, room temperature
• 3 cups buttermilk
• 6 teaspoons baking powder
• 2 teaspoons salt
• 2 teaspoons espresso powder (or instant coffee)
• 2/3 cup butter
• 2 tablespoons vanilla extract
• Peanut butter cups for garnish (optional)

For the peanut butter buttercream

• 1 pound (4 sticks) unsalted butter, softened
• 2/3 cup peanut butter
• 3 cups powdered sugar
• 1/4 cup heavy cream

How to make chocolate peanut butter cake

The steps are straightforward. Read through before starting so you have everything prepped for a smooth bake:

1. Prep – Preheat the oven to 350°F. Grease two 9-inch round cake pans and line the bottoms with parchment circles.
2. Whisk dry ingredients – In a large bowl, whisk together the flour, sugar, cocoa powder, baking powder, and salt.
3. Set up a double boiler – Place 2 inches of water in a saucepan and bring to a simmer. Reduce heat to maintain a gentle simmer and set a glass or metal bowl on top so the bottom doesn’t touch the water.
4. Combine the wet ingredients – In the bowl over the simmering water, whisk the butter and buttermilk until the butter melts. Add the espresso powder, eggs, and vanilla and whisk until combined.
5. Mix – Pour the wet mixture into the dry ingredients and whisk until smooth. Fold in the chocolate chips.
6. Bake – Divide the batter between the prepared pans and bake about 1 hour, or until a knife inserted into the center comes out clean.
7. Make the frosting – While the cakes bake, add the softened butter, peanut butter, powdered sugar, and heavy cream to a stand mixer fitted with the whisk or paddle attachment. Start on low to combine, then beat on medium-high until smooth and fluffy.
8. Cool – Let the cakes cool in the pans for 30 minutes, then run a knife around the edges and invert onto a wire rack to finish cooling.
9. Frost – Once completely cool, assemble with a layer of frosting between the cakes. Apply a thin crumb coat and chill 30 minutes, then add a final thick layer of frosting and decorate as desired.

Tips for the best peanut butter frosting

• Choose good peanut butter – Use a natural or high-quality peanut butter with just peanuts and salt for the best flavor and balance.
• Avoid overbeating – Overwhipped frosting can trap air and create visible bubbles. Beat until smooth and fluffy, then stop.
• Softened butter – Let butter come to room temperature so it blends smoothly. About 30 minutes at room temperature is usually enough.

How to assemble a layer cake

Place a dollop of frosting on the first cake layer to anchor the top layer. Stack the second layer, apply a thin crumb coat over the whole cake, and freeze or chill for 30 minutes. This seals in crumbs and makes the final frosting layer clean and easy to smooth. Finish with a thicker, even coat of frosting and garnish with chopped peanut butter cups if desired.

Make-ahead and storage

This cake stores and travels well. Follow these tips for best results:

• Unfrosted layers: Cool completely, wrap in plastic wrap (or parchment then plastic), and store at room temperature for a few days or freeze for longer storage.
• Fully frosted cake: Keep in the refrigerator. Bring to room temperature for 1–2 hours before serving for best texture and flavor.
• Freezing: Wrap unfrosted layers tightly in parchment and plastic and freeze up to 3 months. Thaw in the refrigerator for a day or two before frosting.

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Dessert recipes

Looking for more dessert inspiration?

Best Chocolate Layer Cake with Peanut Butter Frosting

This isn’t your typical chocolate cake. It’s dense, not-too-sweet, and incredibly satisfying.

By Cassy Joy Garcia

Prep: 25 mins | Cook: 1 hr | Total: 1 hr 25 mins

Servings: 10

Ingredients

For the cake

• 4 cups all-purpose or gluten-free flour
• 4 cups white sugar
• 1 cup cocoa powder
• 2 cups chocolate chips
• 4 eggs, room temperature
• 3 cups buttermilk
• 6 teaspoons baking powder
• 2 teaspoons salt
• 2 teaspoons espresso powder
• 2/3 cup butter
• 2 tablespoons vanilla extract
• Peanut butter cups, for garnish (optional)

For the peanut butter buttercream

• 1 pound butter, softened
• 2/3 cup peanut butter
• 3 cups powdered sugar
• 1/4 cup heavy cream

Instructions

1. Preheat oven to 350°F. Grease and line two 9-inch round pans with parchment circles.
2. Whisk the flour, sugar, cocoa, baking powder, and salt in a large bowl.
3. Set up a double boiler with 2 inches of simmering water and place a bowl on top so it doesn’t touch the water.
4. Whisk butter and buttermilk in the bowl over the heat until the butter melts. Add espresso powder, eggs, and vanilla and whisk to combine.
5. Pour the wet mixture into the dry ingredients and whisk until smooth, then stir in the chocolate chips.
6. Divide batter between pans and bake about 1 hour, or until a knife inserted in the center comes out clean.
7. While cakes bake, make the frosting: beat butter, peanut butter, powdered sugar, and heavy cream starting on low until combined, then increase speed and beat until smooth.
8. Cool cakes in pans 30 minutes, then run a knife around the edges and transfer to a wire rack to cool completely.
9. Assemble and frost: place a layer of frosting between the cakes, apply a thin crumb coat and chill 30 minutes, then finish with a final layer of frosting and garnish.

Nutrition

Calories: 1070 kcal | Carbohydrates: 194 g | Protein: 17 g | Fat: 29 g | Saturated Fat: 13 g | Sugar: 145 g

Additional info

Course: Dessert

Cuisine: American

Servings: 10

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