Preheat Oven To 400F. In A Saucepan, Mix The Sugar, Lemon Juice, Butter And Rum Together And Simmer For 10 Minutes. Peel The Bananas And Slice Them In Half, Lengthwise. Place Them Cut Side Down, In A Buttered Baking Dish And Pour The Hot Syrup Over Them. Bake For 30 Minutes, Turning Once. Let Cool.