Beat butter and margarine at low speed of an electric mixer until creamy; gradually add sugar, beating well. Combine flour, baking powder, and salt; add to butter mixture. Mix at low speed until blended. Roll dough to 3/8" thickness on a lightly floured surface.
Cut out cookies, using a 3" spade-shaped cookie cutter (or use template on page 149). Place on ungreased baking sheets. Make a hole in "socket end" of each cookie, using a straw.
Bake at 350° for 16 minutes. Let cookies cool on wire racks.
Spread Frosting on the "bulb end" of each cookie, using the back of a small spoon. Place frosted cookies on wire racks to dry. When frosting is dry, brush "socket end" of each cookie with melted chocolate, using a small brush. Let dry. When cookies are completely dry, lace licorice strips through holes in cookies. Place tissue in a large flat box, if desired. Arrange cookies in a loose circle on tissue paper to resemble a string of Christmas lights.
Note: Use these cookies as tree ornaments or as edible place cards at a children's party. Write names on frosted cookies using tubes of decorating gel.