Basic Bechamel Sauce (White Sauce) with Variations. - Bechamel (more commonly known as white sauce) is one of the five mother sauces. This most basic sauce in cookery is based on a roux, which is equal volumes of butter and flour. To make the sauce, a liquid (milk, cream or broth) is added and in just a few minutes, the liquid thickens nicely into a creamy sauce. Bechamel is used as the base for favorite dishes such as scalloped or au gratin potatoes and macaroni and cheese.