2 lbs. ground beef
1/4 lb. of mushrooms, thinly sliced (1 c.)
1 tsp. oregano
1 tsp. garlic (or 2 crushed cloves)
2 pkgs. frozen chopped spinach (10 oz. each)
1 pt. dairy sour cream or 1 pt. plain yogurt
1 tsp. salt
1/2 tsp. pepper
1/2 c. shredded Mozzarella cheese
1 can condensed cream of celery soup

Brown beef in large skillet over moderate heat. Add mushrooms, garlic and oregano and stir fry about 5 minutes until mushrooms are lightly brown. Add spinach and heat until thawed and almost all juices have cooked away (about 10 minutes). Stir in soup, yogurt (or cream) salt and pepper. Spoon the mixture into a lightly greased shallow (2 1/2 to 3 quart) casserole. Scatter cheese evenly over top. (At this point you can cover the casserole and refrigerate it until about 45 minutes before serving.) Bake, uncovered in a 350 degree oven for 30 minutes or until bubbly. Serves 6.