Combine the ingredients in a saucepan or rice cooker, except set the cinnamon aside. Stir until mixed. Turn your rice cooker on and watch the rice pudding every ten minutes or so. It will thicken with the "warm" setting. If you use a saucepan, you will bring it to a boil, and then simmer until thickened about 50-60 minutes. When ready to serve, sprinkle with cinnamon as a garnish, if desired.