The Collaborative International Dictionary
Gratinate
Gratinate \Grat"i*nate\, v. t. [F. gratiner, v.i., to form a crust.] (Cookery) To cook, as macaroni, in a savory juice or sauce until the juice is absorbed and a crisp surface forms.
Wiktionary
gratinate
vb. (label en transitive intransitive cooking) To bake so as to form a gratin.