Ingredients
For the Dark Cocoa Cake:
- 1¾ cups all-purpose flour
- 2 cups granulated sugar
- ¾ cup unsweetened dark cocoa powder
- 2 teaspoons baking soda
- 1 teaspoon baking powder
- 1 teaspoon salt
- 2 large eggs, room temperature
- 1 cup buttermilk, room temperature
- 1 cup strong black coffee, hot
- ½ cup vegetable oil
- 1 teaspoon vanilla extract
For the Dark Chocolate Ganache:
- 12 oz dark chocolate (70% cocoa), finely chopped
- 1½ cups heavy cream
- 3 tablespoons unsalted butter, room temperature
- 2 tablespoons light corn syrup
- 1 teaspoon vanilla extract
For Assembly:
- 1-2 teaspoons flaky sea salt (such as Maldon)
- Additional cocoa powder for dusting (optional)
Equipment Needed
- Two 9-inch round cake pans
- Electric mixer (stand or hand mixer)
- Medium saucepan
- Large mixing bowls
- Wire cooling racks
- Offset spatula
Instructions
Prepare the Cake:
- Preheat and prep: Preheat oven to 350°F (175°C). Grease two 9-inch round cake pans and dust with cocoa powder, tapping out excess.
- Mix dry ingredients: In a large bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt.
- Combine wet ingredients: In another bowl, whisk together eggs, buttermilk, hot coffee, oil, and vanilla extract until well combined.
- Make batter: Pour the wet ingredients into the dry ingredients and mix until just combined. The batter will be thin – this is normal.
- Bake: Divide batter evenly between prepared pans. Bake for 30-35 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.
- Cool: Cool in pans for 10 minutes, then turn out onto wire racks to cool completely.
Make the Ganache:
- Heat cream: In a medium saucepan, heat heavy cream over medium heat until it just begins to simmer (small bubbles around the edges).
- Melt chocolate: Place chopped chocolate in a large bowl. Pour hot cream over chocolate and let sit for 2 minutes.
- Whisk ganache: Starting from the center, whisk in small circles, gradually working outward until smooth and glossy.
- Finish ganache: Whisk in butter, corn syrup, and vanilla until fully incorporated.
- Cool: Let ganache cool at room temperature for 30-45 minutes, stirring occasionally, until it reaches a spreadable consistency.
Assemble the Cake:
- Level cakes: If needed, level the cake layers with a serrated knife.
- First layer: Place one cake layer on serving plate. Spread about 1 cup of ganache evenly over the top.
- Second layer: Place second cake layer on top and gently press down.
- Frost: Spread remaining ganache over top and sides of cake, using an offset spatula for smooth finish.
- Add sea salt: Sprinkle flaky sea salt evenly over the top of the cake.
- Final touch: Lightly dust with cocoa powder if desired.
Tips for Success
- Room temperature ingredients: Ensure eggs and buttermilk are at room temperature for better mixing
- Don’t overmix: Mix cake batter just until combined to avoid tough cake
- Hot coffee trick: The hot coffee enhances the chocolate flavor and creates a moist texture
- Ganache consistency: If ganache becomes too thick, gently warm it; if too thin, let it cool longer
- Make ahead: Cake layers can be made 1 day ahead and wrapped tightly
- Storage: Store covered at room temperature for up to 3 days
Serving Suggestions
Serve slices with a glass of cold milk, a cup of coffee, or a scoop of vanilla ice cream. The sea salt perfectly balances the rich chocolate and creates an elegant finish.
Pro tip: Let the cake sit for at least 2 hours after assembly before serving to allow the flavors to meld together.