PREPARE 40 cookies according to package directions. Let stand for 2 minutes; remove to wire racks to cool completely.
MEANWHILE, DIVIDE frosting into smaller bowls. Tint frosting to desired shades with food coloring. Cut licorice into 1 1/2-inch pieces for legs. A total of 160 legs are needed if making all 20 spiders.
SPREAD bottoms of 20 cookies with frosting. Top with remaining 20 cookies. Insert 4 licorice pieces into each side of each spider body.
FOR eyes and fangs, pinch off small pieces of Laffy Taffy; stretch and form into 40 1/2-inch flat circle and 1/2-inch long fangs, if desired. Lightly press Laffy Taffy eyes onto cookies; insert fangs into frosting. For pupils, dip bottom of mini morsels into frosting and then onto eyes. Insert fangs into frosting.