Roux

Roux (/ˈruː/) is flour and fat cooked together and used to thicken sauces. The fat is butter in French cuisine, but may be lard or vegetable oil in other cuisines. The roux is used in three of the mother sauces of classical French cooking: béchamel sauce, velouté sauce, and espagnole sauce. Clarified butter, vegetable oils, bacon drippings or lard are commonly used fats. It is used as a thickener for gravy, other sauces, soups and stews. Roux is typically made from equal parts of flour and fat by weight.

In Cajun cuisine, roux is made with bacon fat or oil instead of butter and dark brown in color, which lends much richness of flavor, albeit less thickening power. Central European cuisine uses lard (in its rendered form) or more recently vegetable oil instead of butter for the preparation of roux (which is called zápražka in Slovak, jíška in Czech, zasmażka in Polish, zaprška in Bosnian, Croatian, Serbian, and Macedonian, "zaprazhka" or "запръжка" in Bulgarian, rántás in Hungarian and Mehlschwitze in German). Further, Japanese Curry, or karē (カレー^?), is made from a roux made by frying yellow-curry powder, butter or oil, and flour together. The French term roux has become a loan-word in Japanese, rū (ルー), or more specifically karērū (カレールー, curry roux^?). Roux (meyane) has been used in Ottoman and Turkish cuisine since at least the 15th century.

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