8 oz. elbow macaroni
2 tbsp. flour
2 tbsp. butter
2 1/3 c. skim milk
3/4 to 1 lb. American cheese

Boil the elbow macaroni for 2/3 the time directed on box. Drain. Make a roux with the flour and butter. Cook in saucepan over medium- low heat for 3 to 4 minutes, stirring often. Add milk; raise heat to medium. Add cheese, a few slices at a time, stirring now and then until sauce is smooth. Put macaroni in a casserole dish. Pour sauce over. Bake, uncovered at 375 degrees for 20 to 25 minutes.