Melt butter, rum, and maple syrup in small bowl in microwave.
Add the lemon juice to the sauce and heat for 30 seconds.
Slice bananas in half width-wise and then in half length-wise so that you have 4 pieces from each banana.
Pour a small amount of the sauce in the bottom of an individual baking dish. Add 2 slices of bananas to each baking dish. Turn the bananas over so that both sides have been coated with the sauce. Bake at 350 degrees for 15 minutes.
Put a coffee measure scoop of Ben and Jerry's vanilla ice cream on top of each dish of bananas. Add a small dollop of whipped cream, a drizzle of caramel sauce, and a small dash of cinnamon. Serve immediately.