Mocha Layer Cake with Silky Coffee Buttercream Frosting

This mocha layer cake packs coffee flavor into every component: coffee in the cake, a coffee syrup brushed into the layers, generous coffee frosting, and a semi-sweet ganache finish.

5 from 3 votes

Ingredients

Cake

• 3/4 cup butter
• 1 cup strong coffee
• 2 tablespoons vegetable oil
• 3/4 cup unsweetened cocoa powder
• 1 cup full-fat sour cream
• 2 teaspoons vanilla extract
• 2 cups cake flour
• 1 1/2 cups granulated sugar
• 1 1/2 teaspoons baking soda
• 1/2 teaspoon baking powder
• 1/2 teaspoon salt
• 1 teaspoon espresso powder
• 2 large eggs, lightly beaten

Coffee Frosting

• 2 cups butter, room temperature
• 6 tablespoons instant coffee granules
• 6 teaspoons water
• 6 cups powdered sugar
• 5 tablespoons whole milk

Ganache

• 1 cup semi-sweet chocolate chips
• 1/2 cup heavy cream
• Pinch of salt
• Coffee syrup, for brushing the cakes

Instructions

Cake

1. Preheat the oven to 350°F. Grease three 8-inch round cake pans and line the bottoms with parchment circles.
2. In a microwave-safe bowl combine the butter and strong coffee. Microwave about 2 minutes, until the butter is melted.
3. Whisk in the vegetable oil and cocoa powder until smooth.
4. Stir in the sour cream and vanilla until fully incorporated.
5. In a large bowl whisk together cake flour, sugar, baking soda, baking powder, salt, and espresso powder.
6. Pour the cocoa mixture into the dry ingredients and add the lightly beaten eggs. Whisk until most lumps disappear and ingredients are combined.
7. Divide the batter among the three prepared pans. Use baking strips if you prefer even layers.
8. Bake 24–26 minutes, or until a toothpick comes out clean or with moist crumbs. Allow cakes to cool in the pans for about 15 minutes, then transfer to a rack to cool completely.

Frosting

1. Beat the room-temperature butter until creamy using a hand mixer.
2. In a small bowl dissolve the instant coffee in the water.
3. Add the coffee mixture and powdered sugar to the butter and mix until combined.
4. Mix in the milk and continue beating about 2 minutes until the frosting is light and fluffy.

Ganache

1. Combine chocolate chips, heavy cream, and a pinch of salt in a microwave-safe bowl.
2. Microwave in 30-second intervals, stirring between each, until smooth and fully combined.
3. Chill in the refrigerator for 30 minutes to an hour until it thickens to a spreadable consistency.

Assemble

1. Level the cake layers if needed so they stack evenly.
2. Brush 2–3 tablespoons of coffee syrup over the first layer of cake.
3. Spread a generous, even layer of coffee frosting, creating a flat surface for the next layer.
4. Repeat brushing, frosting, and stacking with the second layer. Place the final layer on top and brush with more coffee syrup.
5. Apply a thin crumb coat of frosting to seal in crumbs, then chill about 10–15 minutes to set the crust.
6. Add more frosting to the top and smooth the sides with an offset spatula or bench scraper until even.
7. For a ganache drizzle, put the ganache into a small bag, snip a corner, and pipe along the top edge so it drips down slightly. For a ganache shell, chill the ganache until spreadable and smooth it over the sides.
8. Reserve remaining frosting in a piping bag fitted with a large tip and pipe swirls on the top, if desired.
9. Slice and serve. Store in a cool place or refrigerate.

Nutrition

(Nutrition facts are estimates and not guaranteed to be accurate. Consult a registered dietitian for special dietary advice.)