Melt butter in a medium pan over medium heat. Add sliced bananas and brown sugar. Stir (or is you are talented - or don't mind making a mess - toss it all together in the pan) the bananas so they are all equally covered in brown sugar and butter. Cook bananas until caramelized (about 3-5 minutes). Pour into a bowl and set aside to cool.

Once the bananas have been cooled, add bananas, rum, ice cream, milk, cinnamon, and nutmeg to a blender. Blend until all ingredients are combined. Serve in glasses with a pinch of nutmeg on top and garnish with a slice of banana. You can of course add whipped cream to up the richness if you so desire!