Preheat your oven to 350°F (175°C).
Grease and flour two 9-inch round cake pans.
In a large mixing bowl, sift together flour, cocoa, baking soda, baking powder, and salt.
In a separate bowl, whisk together sugar, buttermilk, vegetable oil, eggs, vanilla, and red food coloring until smooth.
Gradually add the dry ingredient mixture to the wet ingredients, alternating with the cooled coffee, mixing until just combined.
Pour the batter evenly into the prepared pans.
Bake for 25-30 minutes, or until a toothpick inserted comes out clean.
Let the cakes cool in pans for 10 minutes, then turn out onto wire racks to cool completely.
For the frosting, beat heavy cream, powdered sugar, and espresso powder until stiff peaks form.
Frost the top of one cake layer, place the second layer on top, and frost the top and sides of the cake.
Garnish with cocoa powder or chocolate shavings, if desired, before serving.