678. Macaroni au Gratin.—Proceed the same as above; but after you have put the macaroni on the dish, omit the gravy, and cover it slightly with bread-crumbs, and about the same quantity of Parmesan cheese grated, a little butter, and then put in a hot oven for a quarter of an hour; if not hot enough, pass the salamander over it, and serve very hot.