1-1 1/2 cups uncooked macaroni (about 6 oz)
1/4 cup margarine OR butter
1 small onion, chopped (about 1/4 cup)
1/2 teaspoon salt
1/4 teaspoon pepper
1/4 cup flour
1 3/4 cups milk
8 ounces swiss cheese, cut into cubes

cook macaroni; drain. cook and stir margarine, onion, salt and pepper over medium heat until onion is tender. blend in flour. cook over low heat, stirring constantly. boil and stir 1 minute. remove from heat. stir in cheese until melted. place macaroni in ungreased 1 1/2 qt casserole dish. stir cheese sauce into macaroni. cook, uncovered, in 375° oven for 30 minutes.