Bechamel is a classic white sauce made from a simple mixture of butter, flour, and milk. It serves as a base for many dishes, including lasagna, macaroni and cheese, and various creamy sauces. The sauce is thickened by cooking equal parts of butter and flour together, known as a roux, before gradually adding milk and stirring until smooth. This versatile sauce is one of the five mother sauces in classical French cuisine, alongside velouté, espagnole, hollandaise, and tomato sauce. Bechamel can be flavored with ingredients like nutmeg or cheese, enhancing its use in a variety of recipes.