In the top of a double boiler, cook until the mixture coats the back of a spoon (about 5 minutes).

Soften gelatine in a small amount of cold water. Add softened gelatine to egg mixture. Stir in vanilla.

Refrigerate until mixture has slightly thickened. Sprinkle bananas with lemon juice and add with pineapple to the thickened custard. Fold in stiffly beaten egg whites. Turn mixture into pie crust. Sprinkle graham cracker crumbs over top, if desired. Refrigerate for several hours or until firm before serving.

Servings: 8.