Cheese souffle

3 tbsp. butter
3 tbsp. flour
1/2 tsp. salt
pinch of dry mustard
pinch of pepper
1 cup milk
1 cup shredded cheese
3 egg yolks.
3 egg whites.
4 to 5 servings
Melt butter.
Blend in flour, salt, dry mustard and pepper.
Gradually stir in milk.
Cook over medium heat until thickened.
Add cheese.
Stir until cheese melts.
Remove from heat.
Beat until light 3 egg yolks.
Beat until stiff 3 egg whites.
Carefully fold in cheese mixture.
Bake in ungreased 1 1/2qt. casserole for 1 hour or until set and lightly browned.