1/4 c. butter
1/4 c. flour
1/2 tsp. salt
1 c. milk
1 c. cheese
4 egg whites
4 egg yolks

In saucepan, melt butter, blend in flour, salt, and milk all at once. Cook and stir until thickened and bubbly. Remove from heat; stir in cheese until melted, and stir in egg yolks. Beat egg whites until stiff peaks form, about 1 1/2 minutes on medium speed. Slowly add cheese mixture over beaten egg whites. Fold together. Bake at 350 degrees until knife inserted in center comes out clean, approximately 1 hour. Serve immediately.