*Heat the butter or margarine in a saucepan.
Stir in the flour, then gradually blend in the milk.
Cook until a thick sauce is formed and season well.
Remove from the heat and add the egg yolks, then the hard boiled eggs cut in pieces or cheese.
Fold in the stiffly beaten egg whites.
Put into a greased souffle dish. Bake in the oven at 375-400 degrees for 30 min until brown and risen.
Serve hot.