Preheat oven to 350
Cream the butter and sugar
Add eggs and vanilla
Stir in cornstarch, baking soda, baking powder, and cocoa powder
In a separate bowl mix the filling ingredients together
Scoop the dough and flatten into discs
Use a ½ tbsp scoop to scoop the filling
Put the filling on top of a disc
Put a disc on top of the filling
Press the sides together
Complete for all the dough and filling
Bake for 9-13 minutes