Brown sausage in skillet, stirring to crumble. Drain off fat and set sausage aside. Beat eggs until lightly colored. Add bread crumbs, milk, salt, dry mustard and sausage. Stir in cheese. Spoon into ungreased 1-quart souffle dish. Cover and refrigerate overnight. The next day bake at 325F 1 hour and 15 minutes, or until knife inserted in center comes out clean. Serve immediately.