Ingredients
Method
- Preheat the Oven: Preheat oven to 350°F (175°C). Grease and line two 9-inch round cake pans with parchment paper.
- Melt the Chocolate: In a heatproof bowl, melt 6 oz of dark chocolate over a double boiler or in the microwave in 30-second intervals until smooth. Set aside to cool slightly.
- Cream the Butter and Sugars: In a large mixing bowl, beat the butter, granulated sugar, and brown sugar until light and fluffy, about 3–4 minutes.
- Add Eggs and Vanilla: Beat in the eggs one at a time, followed by the vanilla extract. Mix until well combined.
- Combine Dry Ingredients: In a separate bowl, whisk together flour, cocoa powder, baking soda, baking powder, espresso powder, and salt.
- Alternate Wet and Dry: Add the dry ingredients to the wet mixture in three additions, alternating with the buttermilk. Mix gently until just combined, then fold in melted chocolate and chocolate chips.
- Bake: Divide the batter evenly between prepared pans and bake for 35–40 minutes, or until a toothpick inserted into the center comes out clean. Cool in pans for 10 minutes, then transfer to a wire rack.
- Prepare the Ganache: Heat the heavy cream in a small saucepan until just simmering. Pour over chopped dark chocolate and let sit for 2–3 minutes. Add butter, vanilla, and corn syrup (if using), then stir until smooth and glossy.
- Assemble and Frost: Once cakes are fully cooled, spread a layer of ganache between the layers and over the top and sides of the cake. Let set before slicing.
Notes
For an extra rich flavor, use espresso powder and high-quality chocolate. This cake keeps beautifully for up to 3 days at room temperature or 5 days refrigerated. You can also freeze layers before frosting for up to 2 months. For a dairy-free option, substitute plant-based butter and cream.