Ingredients:

3 tablespoons butter or margarine
3 tablespoons flour
1/2 teaspoon dry mustard
dash of red pepper
1/2 teaspoon salt
1 cup milk
1/2 pound process American cheese shredded
4 egg yolks, beaten until thick and lemon colored
4 egg whites, stiffly beaten

Directions:

Melt butter in a saucepan, add flour, mustard, red pepper and salt and blend. Add milk all at once and cook and stir over moderate heat until the resulting sauce is smooth and thickened. Remove from the heat, add the shredded cheese and stir until the cheese is melted. Add egg yolks and blend well. Fold in egg whites, lightly and thoroughly. Pour mixture into an ungreased 1 1/2 quart casserole or baking dish, set in a shallow pan of hot water and bake in a 325-degree F. oven for 50 minutes to 1 hour, or until a knife inserted is the center comes out clean. Serve at once.