Set your oven to 350°F. Prepare two nine inch round cake pans by greasing each pan and lining the bottom with parchment paper.

In a very large mixing bowl, combine flour, sugar, cocoa powder, baking soda and salt. Mix until blended.

In another bowl, mix eggs, buttermilk, oil, and vanilla. Combine wet ingredients into dry ingredients. Pour coffee slowly while gently stirring the batter. Batter will now appear to be smooth and consistent.

Divide batter equally among prepared pans. Baking will take approximately thirty-five minutes depending on the size of your pans. A toothpick inserted into the middle will come out clean if it is done.

Remove from heat after ten minutes and allow cakes to cool slightly on a wire rack. Once cooled, remove from pans and transfer to wire racks to complete the cooling process.

Combine softened butter, confectioner's sugar, cocoa powder, heavy cream, and additional vanilla extract in a large bowl. Using high speed, beat until light and fluffy.

Using a single cooled cake layer, apply an equal amount of frosting to the top. Then using the second layer, apply the second layer on top of the first layer. Apply frosting to the entire cake surface.