LINE an 8- x 8-inch baking pan with Reynolds Parchment Paper, extending paper up sides of pan.
PREPARE brownie mix following package directions; stir in nuts and coconut. Spread batter evenly in parchment-lined pan.
BAKE following brownie package. Cool completely.
SPREAD chocolate frosting over cooled brownie. Squeeze softened vanilla frosting in 6 to 8 lines crosswise over chocolate frosting, spacing lines 1 inch apart. Using a wooden pick, draw lines through frosting alternating direction to create a marbled pattern. Cut into bars.
REYNOLDS KITCHENS TIP:
*Place vanilla frosting in a plastic food storage bag; leave unsealed. Microwave on HIGH 5 seconds. Squeeze bag to remove air pockets. Seal bag, snip 1 bottom corner; squeeze onto brownies.