Au gratin dish

Gratin (French pronunciation: ​[ɡʁatɛ̃]) is a widespread culinary technique in which an ingredient is topped with a browned crust, often using breadcrumbs, grated cheese, egg and/or butter. Gratin originated in French cuisine and is usually prepared in a shallow dish of some kind. A gratin is baked or cooked under an overhead grill or broiler to form a golden crust on top and is traditionally served in its baking dish.

A gratin dish refers to the shallow oven-proof container traditionally used to prepare gratins and similar dishes.

The etymology of gratin is from the French language words gratter, meaning "to scrape" or "to grate" (for example, "scrapings" of bread or cheese), and gratiné, from the transitive verb form of the word for crust or skin. The technique predates the current name which did not appear in English until 1846 (OED, s.v. "gratin").

In addition to the well-known potato dishes such as Gratin dauphinois, cooking au gratin is a widely used cooking technique in the preparation of numerous dishes including many meat, fish, vegetable and pasta dishes, fennel, leeks, crab meat, celeriac and aubergines (eggplant).

The term le gratin signifies the "upper crust" of Parisian society, and, as gratin, has since been borrowed into English.

Potatoes gratiné is one of the most common of gratins and is known by various names including "gratin potatoes" and "Gratin de pommes de terre". Slices of boiled potato are put in a buttered fireproof dish, sprinkled with cheese and browned in the oven or under the grill. In North America, the dish is referred to variously as scalloped potatoes, potatoes au gratin, or au gratin potatoes. (Note that the term scalloped originally referred to a style of seafood dish rather than to one specifically based on the scallop.) In French-speaking Canada, the dish is referred to as patates au gratin. Australians and New Zealanders refer to it as scalloped potatoes or potato bake.

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