1. Combine sweet potatoes, 4 tablespoons of the margarine, salt and spices. Beat until smooth. Stir in 1 cup of the marshmallows. Spread in 10 x 6 x 2-inch (1 1/2-quart) glass baking dish coated with cooking spray, or individual dishes. Top with remaining marshmallows. 2. Melt remaining margarine. Combine with KELLOGG'S RICE KRISPIES cereal and brown sugar. Sprinkle over marshmallows. 3. Bake at 350° F about 20 minutes or until hot and cereal is golden brown. Serve hot.