3 tablespoons butter
3 tablespoons flour
3/4 teaspoon salt
3/4 cup milk
1 cup (4 ounces) shredded Wisconsin sharp cheddar cheese
3 eggs, separated
1 teaspoon chopped chives
Melt butter in saucepan over low heat. Blend in flour and salt. Slowly add and stir in milk. Cook, stirring constantly, until mixture thickens. Add cheese. Heat and stir only until cheese melts; remove from heat.
Beat egg whites until stiff but not dry. Beat egg yolks; slowly add the cheese sauce to the egg yolks and beat until fluffy. Fold the chives and cheese-egg mixture into beaten egg whites.
Turn into buttered casserole. Place casserole in a pan filled with hot water and bake at 350° F for 45 minutes or until soufflé extends above the casserole and is slightly browned.