Rice pudding is a sweet and creamy dessert that's perfect for using up leftover rice. To make it, combine 2 cups of cooked rice, 2 cups of milk, 1/2 cup of sugar, and 1/2 teaspoon of cinnamon in a pot. Bring to a boil, then reduce the heat and simmer for 20-25 minutes, or until the mixture has thickened and the rice is tender. Stir in some raisins or chopped nuts if desired, and serve warm or chilled.