Preheat your oven to 325°F (165°C).
In a large bowl, whisk together buttermilk, eggs, and vanilla extract until well combined.
In a separate bowl, sift together cocoa powder, flour, baking soda, and baking powder. Then whisk in the sugar.
Gradually combine the dry ingredients with the buttermilk mixture, mixing until just combined.
Slowly add the hot coffee to the batter, mixing until smooth but be careful not to overmix.
Line cupcake tins with paper liners and fill each one about 2/3 full with batter.
Bake for 16-18 minutes or until a toothpick inserted into the center comes out clean.
Allow the cupcakes to cool completely before assembling.