2 sm. cans frozen pineapple juice
2 sm. cans frozen limeade concentrate
2 sm. cans frozen lemonade concentrate
5 qt. 7-Up, chilled

Combine concentrates. (Use mixer, if desired, to blend well.) Tint with food coloring to a deep shade of green. Pour into 2 or 3 small molds or 1 large mold and freeze. At serving time, dip 1 mold at a time into warm water. Unmold into punch bowl. Slowly pour 1/2 of the 7-Up over the concentrate; stir gently. If desired, garnish with lemon and lime slices.