Take 2 ripe, but not soft bananas and cut in half, then split lengthwise. Melt a few Tablespoons butter over medium heat. Add 2-3 T brown sugar and stir. Add bananas. Cook until fairly warm and starting to soften (about 1 min.). Flip bananas and allow to cook an additional 30 seconds. Add rum (light or dark; dark has more flavor) to taste, and swirl in pan a bit. Allow to thicken slightly, remove from heat and serve.