1Mix together the cake mix, eggs, water, cooking oil and cocoa until you can shape it all into a large ball. Let stand 20 minutes.
2Shape into 1/2 inch balls, placed 2 inches apart on greased cookie sheets. Flatten each cookie with bottom of glass greased once but dipped into instant chocolate drink powder.
3Bake at 400 degrees F (205 degrees C) for 8 minutes. Remove cookies at once and quickly flatten each with back of spatula. Let cool 20 minutes.
4To make filling: Soften 1 envelope unflavored gelatin in 1/4 cup cold water; set in heatproof cup in pan, simmering until clear. Cream together shortening, confectioners' sugar and vanilla. Add cooled gelatin. Beat 10 minutes. Use 1 tablespoon to fill each cookie. Press cookies gently together to spread the filling.