Ingredients
For the Cake
- 2 cups all-purpose flour
- 3/4 cup black cocoa powder
- 1 cup buttermilk, room temperature
- 1 cup hot strong coffee
- 1.5 cups softened butter
- Oil, eggs, and vanilla (quantities estimated below)
- 1 1/2 cups granulated sugar (estimated)
- 2 large eggs (estimated)
- 1/4 cup vegetable oil (estimated)
- 1 teaspoon vanilla extract (estimated)
For the Blackberry Compote
- 2 cups blackberries
- 1/2 cup granulated sugar (estimated)
- 1 tablespoon lemon juice (estimated)
- 1 tablespoon cornstarch slurry (cornstarch mixed with water)
For the Frosting
- 1.5 cups softened butter
- 4 cups powdered sugar
- 3/4 cup black cocoa powder (estimated to incorporate black cocoa flavor in frosting)
- 2-3 tablespoons heavy cream or milk (estimated to adjust consistency)
Instructions
- Prepare the Blackberry Compote: In a saucepan over medium heat, combine the blackberries, sugar, and lemon juice. Simmer the mixture until it begins to thicken, stirring occasionally. Add the cornstarch slurry and bring to a boil for 1 minute to activate the thickening agent. Remove from heat and let it cool completely to room temperature.
- Mix the Cake Batter: In a large bowl, whisk together the all-purpose flour, black cocoa powder, and sugar. In a separate bowl, combine the buttermilk, eggs, vegetable oil, and vanilla extract. Gradually add the wet ingredients to the dry ingredients, stirring gently to combine. Slowly stir in the hot coffee to ensure the batter is smooth and evenly mixed.
- Bake the Cake: Preheat the oven to 350°F (175°C). Grease and flour two 9-inch round cake pans. Divide the batter evenly between the pans and bake for 30 to 35 minutes or until a toothpick inserted in the centers comes out clean. Allow the cakes to cool completely on a wire rack before frosting.
- Prepare the Frosting: Using a mixer, beat the softened butter until creamy. Gradually add powdered sugar and black cocoa powder, mixing well after each addition. Add heavy cream or milk a tablespoon at a time until the frosting reaches a fluffy and spreadable consistency.
- Assemble the Cake: Place one cake layer on a serving plate. Spread a frosting dam (a thick border of frosting) around the edges to contain the filling. Spoon the cooled blackberry compote into the center. Top with the second cake layer. Frost the entire exterior of the cake smoothly with the remaining frosting. Decorate the top with fresh blackberries for garnish.
Notes
- Ensure the coffee is hot when added to the cake batter to help intensify the chocolate flavor and keep the batter smooth.
- The frosting dam prevents the compote from leaking out the sides during assembly.
- Use room temperature ingredients for better mixing and texture.
- Black cocoa powder gives the cake its characteristic deep black color; do not substitute with regular cocoa powder.
- Store the cake refrigerated due to the buttercream and compote filling. Allow to come to room temperature before serving for best flavor.
- Prep Time: 30 minutes
- Cook Time: 35 minutes
- Category: Dessert
- Method: Baking
- Cuisine: American