Avoid using aluminium utensils. It is quicker and easier to pour boiling milk onto a cold roux: if the milk is poured on cold, the mixture must be stirred constantly until it boils and throughout the cooking.
It is also called by its Italian name, balsamella. The thickness of the sauce depends on the proportion of flour and butter (roux) to milk. The proportions for a thin sauce would be 1 tablespoon each of butter and flour per 1 cup of milk; a medium sauce would use 2 tablespoons each of butter and flour; a thick sauce, 3 tablespoons each.
In France, it is one of the four basic sauces called "meres" or "mother sauces" from which all other sauces derive. It is a smooth, white sauce made from finely chopped vegetables and herbs which are infused in milk and thickened with a roux made with flour, boiled milk, and butter. It is usually served with white meats, eggs, and vegetables. It forms the basis of many other sauces.
Béchamel Sauce (from Carème's recipe). Reduce the velouté until it is thick, then blend it with egg yolks and thick cream. Stir with a wooden spoon to make sure the suace does not stick to the pan. Remove it from the heat, add a piece of butter the size of a walnut and a few tablespoons of double heavy cream. Add a pinch of grated nutmeg, sieve through muslin (cheesecloth) and keep hot in a bain-marie.
