Heat 1 cup milk 2 minutes on medium high; set aside. Melt 2 tablespoons butter 1 minute on high. Stir in 2 tablespoons flour, heat 1 minute more on high. Briskly stir in warm milk. Blend well. Cook on high 2 1/2 minutes or until boiling. Stir in 1 cup grated cheddar cheese; blend well.