Spinach Souffle

Directions

1. 1
   Melt butter; stir in flour and gradually add milk until mixture thickens.
2. 2
   Stir
3. 3
   in cheese and beaten egg yolks.
4. 4
   Fold in onion
5. 5
   and spinach.
6. 6
   Stir until smooth and slightly cool. Fold stiffly beaten egg whites into mixture.
7. 7
   Bake in buttered casserole at 350°
8. 8
   until firm on top and soft inside, about 35 minutes.