A thickener for savory dishes, made basically from a combination of flour, butter and milk. The thickener is used in sauces such as bechamel sauce, veloute sauce and espagnole sauce. Vegetable oil, bacon drippings and lard can be substitutes for butter. Using oil instead of butter gives it a richer flavor. The color can range from white to nearly black depending on the time it is cooked for.

The cooking ingredients differ based upon the cuisine. In Italian cuisine, equal proportions of butter and flour are taken. In Cajun cuisine, bacon fat or oil is substituted for butter.

Light roux and drak roux are two common varieties of roux available for usage. Light roux provides little flavor but gives richness to a dish, and is used in French cooking and some gravies or pastries throughout the world. The Darker roux is mostly used to add a nutty flavor to a dish There is another type of roux that is prepared by cooking goat milk cream over a low flame with wheat flour or starch.

Tip: When mixing the heated fat and flour, stir until the raw flour taste is no longer present. Roux can be substituted by water and wheat flour.