Potatoes Au Gratin
["1 medium onion, chopped (about 1/2 c.)", "2 Tbsp. butter or margarine", "1 Tbsp. flour", "1 tsp. salt", "1/4 tsp. pepper", "2 c. half and half*", "2 c. shredded natural sharp Cheddar cheese (about 8 oz.)", "6 medium potatoes, sliced", "1/4 c. fine dry bread crumbs"]
["Heat oven to 375\u00b0. Cook and stir onion in butter in 2-quart saucepan until onion is tender. Stir in flour, salt and pepper. Cook over low heat, stirring constantly, until mixture is smooth and bubbly. Remove from heat. Stir in half and half and 1 1/2 cups of the cheese. Heat to boiling, stirring constantly. Boil and stir 1 minute. Place potatoes in ungreased 1 1/2-quart casserole. Pour cheese sauce on potatoes. Bake, uncovered, until top is brown and bubbly, 1 1/4 to 1 1/2 hours."]
["onion", "butter", "flour", "salt", "pepper", "*", "natural sharp", "potatoes", "bread crumbs"]