1 pkg. frozen chopped spinach; cook in salted water and drain

WHITE SAUCE:

3 tbsp. butter
3 tbsp. flour
1 c. milk
3 egg yolks

Mix butter, flour, and milk. Add egg yolks. Add spinach, salt and a little grated onion, 1/2 cup grated cheese. Fold in stiffly beaten egg whites. Bake in casserole, set in pan of hot water about 30 minutes at 350 degrees. 4-6 servings.