This recipe creates an intensely rich, moist, dark chocolate layer cake topped with fudge frosting and a glossy ganache drip for maximum chocolate indulgence.
Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
In a large bowl, whisk together the flour, sugar, cocoa powder, baking soda, baking powder, and salt.
Add the buttermilk, oil, eggs, and vanilla extract to the dry ingredients. Beat with an electric mixer on medium speed for two minutes.
Carefully stir in the hot coffee until the batter is smooth. Stir in the chocolate chips. The batter will be thin.
Divide the batter evenly between the prepared pans. Bake for 30 to 35 minutes, or until a wooden pick inserted into the center comes out clean.
Let the cakes cool in the pans for 10 minutes before inverting them onto a wire rack to cool completely.
Prepare the Fudge Frosting: Beat the softened butter until creamy. Gradually add the powdered sugar and cocoa powder, alternating with the milk/cream, until smooth and spreadable. Add more sugar for thickness or more liquid for thinness.
Prepare the Ganache: Place the chopped bittersweet chocolate in a heatproof bowl. Heat the heavy cream until it just simmers. Pour the hot cream over the chocolate. Let it sit for 5 minutes, then whisk until smooth and glossy. Let the ganache cool slightly until it thickens enough to drip slowly.
Assemble the cake: Place one cooled layer on a serving plate. Spread a thick layer of fudge frosting on top. Place the second layer on top. Frost the top and sides of the entire cake with the remaining fudge frosting.
Pour or spoon the slightly cooled ganache over the top center of the cake, allowing it to drip down the sides. Let the ganache set before slicing.
Notes
Using dark cocoa powder provides a deeper, more intense chocolate flavor for the sponge.
Do not overmix the batter once the wet ingredients are added to keep the cake tender.
If you prefer a firmer drip, chill the cake briefly after applying the ganache.