In a small frying pan, melt the butter and then add the sugar.
Stir quickly to mix together and then add the bananas.
Toss together until all the bananas are coated - for about a minute or so.
Add a splash of rum (how much you want to use is up to you!) and flambé the bananas and carmamel by setting light to it with either a long match, or by tipping the pan to catch the gas ring (if you have a gas hob). After a few seconds the flame will go out.
Serve over warm pancakes, on their own, or with cream or ice-cream.