Cookies:
Preheat oven to 375⁰F.
Combine flour, cocoa, baking soda, salt, and sugar in electric mixer. While mixing, add butter or margarine, and egg.
Place rounded teaspoons on lined baking sheet and bake for 9 minutes at 375⁰F.
Cream Filling:
Combine butter or margarine, shortening, confectioners’ sugar, egg, and vanilla.
Pipe into center of cookies.