2 lbs. ground beef or chuck
1 tbsp. oil
1 c. sour cream
1 can cream of celery soup
1/2 tsp. pepper
6 oz. sliced Mozzarella cheese
1 (8 oz.) can sliced drained mushrooms
1 pkg. frozen spinach, thawed, cooked and drained
1 tsp. garlic salt
5 tsp. minced onion

Brown hamburger and mushrooms in oil; spoon into 2-quart casserole. Stir in remaining ingredients except cheese. Use cheese to make design on top of casserole. Do not cover. Bake at 350 degrees for 45 minutes. Serves 8.