Preheat oven to 350°. Cook and stir meat until browned through; add chopped onion and green pepper and sauté 2 minutes longer. Drain well to remove excess fat. Cook macaroni as directed on package; drain. In ungreased 2-quart casserole, combine browned beef and onions, cooked macaroni, soup, milk, ketcup, cheese, and salt. Cover and bake 35 to 40 minutes. Uncover;
sprinkle with crushed potato chips, and bake 5 minutes longer.
Serves 4.