Step 1: Preheat and Prepare Pans: Preheat oven to 350F (175C). Grease and flour two 9-inch round cake pans. This step is crucial to ensure that the cakes release cleanly after baking.
Step 2: Combine Dry Ingredients: In a large bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt. Ensure that these ingredients are thoroughly combined to create a uniform base for the cake.
Step 3: Mix Wet Ingredients: In a separate bowl, combine the buttermilk, oil, eggs, and vanilla extract. Whisk until well blended. The buttermilk adds a subtle tang that enhances the chocolate flavor.
Step 4: Combine Wet and Dry Ingredients: Gradually add the wet ingredients to the dry ingredients, mixing until just combined. Avoid overmixing, as this can result in a tough cake.
Step 5: Add Boiling Water: Carefully pour the boiling water into the batter and mix until smooth. The addition of boiling water helps to bloom the cocoa powder, intensifying the chocolate flavor. The batter will be thin.
Step 6: Bake the Cakes: Divide the batter evenly between the prepared cake pans. Bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean. Rotate the pans halfway through baking to ensure even cooking.
Step 7: Cool the Cakes: Let the cakes cool in the pans for 10 minutes before inverting them onto a wire rack to cool completely. This prevents the cakes from sticking to the pans.
Step 8: Prepare the Fudge Frosting: In a large bowl, beat the softened butter until creamy. Gradually add the powdered sugar and cocoa powder, beating until well combined.
Step 9: Add Milk and Vanilla: Add the milk, vanilla extract, and salt to the frosting. Beat until smooth and creamy. Adjust the amount of milk to achieve the desired consistency.
Step 10: Assemble the Cake: Place one cake layer on a serving plate. Spread a generous layer of fudge frosting over the top.
Step 11: Stack and Frost: Carefully place the second cake layer on top of the frosting. Frost the top and sides of the cake with the remaining fudge frosting. A smooth, even layer of frosting enhances the presentation.
Step 12: Decorate (Optional): Decorate the cake as desired with chocolate shavings, sprinkles, or fresh berries. A simple yet elegant decoration adds a finishing touch.
For a richer flavor, substitute brewed coffee for the boiling water. Chopped nuts can be added to the frosting for added texture.