Whisk together flour, cocoa, baking soda, baking powder, salt and sugar.
Beat in the butter and egg until dough comes together.
Place between 2 sheets of parchment paper and roll out to between 1/8 and 1/4 inch thick.
Place in freezer for 15 minutes.
Preheat oven to 375.
Use a 2" cookie cutter and make cookies.
Place on parchment lined cookie sheet.
Bake for 9 minutes.
Allow to cool completely.
Cream together butter, vanilla and sugar.
Gradually beat in the sugar.
Continue beating until fluffy.
Transfer filling to piping bag with round tip.
Pipe filling onto a cookie to nearly cover.
Place another cookie on top of the filling and lightly press.