Peel bananas. Heat margarine in large skillet or blazer pan or chafing dish. Turn bananas in margarine and cook 3 or 4 minutes, until golden colored. Sprinkle with brown sugar and turn bananas until bubbling syrup is formed. Add 2 tablespoons rum and baste bananas with sauce. Set aside until ready to serve. Just before serving, warm bananas until sauce is bubbling. Warm remaining quarter cup rum. Pour rum over bananas, ignite, and as flames flicker, serve bananas. Serve alone as dessert or as topping for vanilla or butter pecan ice cream. Slice bananas into small chunks.