Make cake, add 1 egg: separate all eggs and whip whites stiff with cream of tartar, substitute melted butter for the oil. Cut up banana into lg pieces, fold into batter very carefully then fold in egg whites. Pour into parchment lined spring pan bake according to box. Whip whip cream stiff add gelatin which is moistened by water. After cake is cooled slice horizontal spread layer with whipped cream mix cut thin pieces of banana and line layer place other cake layer on top and frost with whipped cream and decorate