Preheat oven to 350 degrees.
Combine sugar, flour, salt, eggs, milk and vanilla in a small non-reactive saucepot. Cook over low heat, stirring constantly until the pudding thickens. Remove from heat and slowly add butter until incorporated.
Butter a two-quart baking dish. Arrange the vanilla wafers around the outside and across the bottom of the baking dish. Spread a layer of custard over the wafers. Place sliced bananas on top of custard and spoon the remaining custard over bananas, spreading evenly.
Using an electric mixer beat the egg whites until they are increase in volume. Add sugar and cream of tartar. Beat to stiff peaks. Spread meringue over pudding and bake 8-10 minutes.
Yield: 8-10 servings