Mix flour, 1/2 cup sugar and salt in top of double boiler, slowly stir in hot milk and cook until mixture thickens, stirring constantly. Stir a little of hot mixture into beaten egg yolks, pour back into double boiler, cook about 2 more minutes.
Remove from heat, add vanilla and cool until just warm. Alternate layers of vanilla wafers, sliced bananas and pudding in a baking dish. Beat 2 egg whites until foamy, add 1/4 cup sugar gradually, beat until stiff. Pile lightly on pudding. Bake in hot 400 degree oven for about 8 minutes or until golden brown.
