In a large skillet melt butter; stir in brown sugar until melted. Add bananas; cook and gently stir over medium heat about 2 minutes or until heated through. Sprinkle with cinnamon. Stir in creme de cacao.
In a saucepan heat rum until it almost simmers. Ignite rum with a long match (see photo, below). Pour over bananas; stir gently to coat. Spoon sauce over ice cream; serve immediately.