In the culinary arts, the word gratin (pronounced "GRAH-tin") can refer to a recipe that is prepared in the au gratin style, which means that it's topped with seasoned breadcrumbs and cheese and then baked. A recipe prepared au gratin is sometimes called a gratinée (pronounced grah-tee-NAY).
The word gratin can also refer to the dish in which a gratinée is baked. A gratin dish is flat and shaped like an oval, with handles on each end.
Vegetables like cauliflower, asparagus, artichokes, leeks or even mushrooms can be prepared au gratin. Perhaps the most popular gratin recipe is Potatoes au Gratin (also called potatoes Dauphinoise). Fish and seafood are frequently prepared au gratin as well.