What is a roux?

A roux is a mixture of flour and fat, commonly butter, that is cooked together to form a thickening agent for sauces, soups, and stews. By combining equal parts flour and fat, typically heated over low to medium temperature, the roux is allowed to cook until it reaches either a pale color for a white roux or a darker color for a brown roux, which adds depth of flavor. This technique is foundational in classical cooking, particularly in French cuisine, where it serves as the base for many classic sauces, such as béchamel and velouté. Understanding how to properly make and utilize a roux is essential for achieving the desired consistency and flavor in various culinary applications, making it an indispensable skill for culinary arts students.