1/2 onion, chopped
1 pkg. frozen chopped spinach, drained well
8 oz. Ricotta cheese
12 oz. muenster cheese (slices)
1 egg

Mix onion, spinach, ricotta cheese and egg in a bowl. Line bottom of 8 1/2 inch pie (or quiche) pan with half of muenster cheese slices. Add the mixture to the pan and top with remaining muenster cheese slices. Bake at 325 degrees for about 40-45 minutes or until brown and bubbly.