Tuna & Spinach Casserole

1 pkg cooked spinach, chopped and seasoned
2 tbs butter
3 tbs flour
2 cans tuna
2 cups milk
1/4 cup grated swiss cheese
1/2 cup grated chedar cheese

Put spinach in a shallow baking dish and keep hot.
Make a white sauce with butter, flour, milk, add swiss cheese and 2 tbs cheddar
cheese, and oil and juice from tuna. Cook over hot water for 20
minutes add tuna, flaked and pour over spinach. Sprinkle with
remaining cheddar cheese and broil until brown and bubbly.