Preheat your oven to 350°F (175°C). Grease and line your cake pans.
In a large mixing bowl, combine the flour, cocoa powder, baking powder, baking soda, and salt by whisking them together until evenly blended.
In another bowl, beat together sugar, eggs, buttermilk, oil, and vanilla.
Slowly add the dry ingredients to the wet mixture, stirring continuously until fully incorporated.
Pour in the hot coffee and stir until the batter becomes smooth and well mixed. Fold in chocolate chips.
Pour the batter evenly into the pans and bake for 30 to 35 minutes.
Cool completely on a wire rack before frosting.
For the frosting, beat butter, cocoa, and powdered sugar. Add milk as needed for smooth consistency. Frost and decorate.
