Spinach Casserole - cooking recipe

Ingredients

1 lb. hamburger
8 oz. sour cream
1 can cream of celery soup
1 small onion
1 small jar mushrooms
1 pkg. shredded Mozzarella cheese
1 pkg. frozen spinach

Preparation

Saute onion and mushrooms in skillet.
Add hamburger and brown. Drain excess liquid.
Place frozen spinach on top and cover.
Let simmer until spinach thaws, then mix with hamburger.