Beef-Spinach Casserole
["1 lb. ground beef", "1/2 medium onion, chopped", "2 small pkg. frozen leaf spinach", "1 can cream of celery soup", "1 c. sour cream", "8 oz. Mozzarella cheese"]
["Saute in skillet until beef and onio are brown and tender. Cook and drain.", "Combine beef, spinach, soup and sour cream. Season to taste.", "Pour into 9 x 13-inch casserole.", "Top with grated cheese and bake at 350\u00b0 for 30", "minutes."]
["ground beef", "onion", "frozen leaf spinach", "cream of celery soup", "sour cream", "Mozzarella cheese"]