In a large bowl, combine flour, cocoa powder, sugar, baking powder, baking soda and salt.
In a separate bowl, combine beaten eggs, buttermilk, melted butter, coffee and vanilla.
Add wet mixture to the dry ingredients and fold in with a spatula until just combined. Allow the mixture to set for a few minutes to thicken.
Heat a large non-stick skillet (or griddle) over medium heat.
Ladle 1/4 cup of pancake batter into the pan and cook until small bubbles begin to form on the surface.
Flip and cook one to two minutes more.
Transfer to a serving plate and repeat for the remaining batter.
Sprinkle with powdered sugar if desired.