Preheat oven to 350°F and line cupcake pans with paper liners.
In a large mixing bowl, cream butter and sugar until light and fluffy.
Add eggs one at a time, beating well after each addition. Stir in vanilla.
In another bowl, whisk flour, cocoa, baking powder, baking soda, and salt.
Gradually add dry ingredients to wet mixture, alternating with buttermilk.
Mix until just combined, then stir in hot coffee.
Pour batter evenly into liners, filling about two-thirds full.
Bake for 18-22 minutes or until a toothpick inserted comes out clean.
Let cupcakes cool completely before frosting with chocolate frosting.
Decorate with sprinkles or toppings as you like.