2 packages lemon Jell-O dissolved in 2 cups boiling water
2 cups 7-Up
2 large bananas, sliced
1 - #2 can crushed pineapple, drained
1 cup small marshmallows

Topping:

1/2 cup sugar
2 tablespoons flour
1 cup pineapple juice
1 egg, beaten
2 tablespoons butter
1 small carton Cool Whip
1/4 cup cheese, shredded

When Jell-O is partially set, add remaining ingredients. Pour into 9 x 13-inch pan and chill until firm.
Topping: Combine sugar and flour in saucepan; stir in pineapple juice and egg. Cook, stirring constantly. Add butter and cool. Fold in Cool Whip and spread over Jell-O and sprinkle with shredded cheese. (The 7-Up keeps the bananas from turning dark.)