Step 1: Preheat the Oven. Preheat your oven to 350°F (175°C). Grease and flour your two 9-inch round cake pans.
Step 2: Mix Dry Ingredients. In a large mixing bowl, combine the flour, sugar, cocoa powder, baking powder, baking soda, and salt. Whisk until well mixed.
Step 3: Add Wet Ingredients. Add the eggs, milk, vegetable oil, and vanilla to the dry ingredients. Beat on medium speed for about 2 minutes until smooth.
Step 4: Incorporate Boiling Water. Carefully stir in the boiling water. The batter will be thin, which is expected.
Step 5: Pour and Bake. Divide the batter evenly between the prepared pans. Bake for 30-35 minutes or until a toothpick comes out clean.
Step 6: Cool the Cakes. Let the cakes cool in the pans for 10 minutes, then transfer to a cooling rack to cool completely.
Step 7: Make the Whipped Chocolate Buttercream. Beat the softened butter until creamy. Gradually add powdered sugar and cocoa, mixing until combined. Add vanilla and 2 tablespoons heavy cream, beating until fluffy.
Step 8: Assemble the Cake. Place one cake layer on a plate, spread buttercream on top, then add the second layer and frost the top and sides.
Step 9: Decorate and Serve. Get creative with decorations like chocolate shavings or sprinkles. Slice and serve to your guests.
