Redefining Cream Soups
The term cream soup once only applied to those soups that were made from a roux base combined with milk to make b�chamel, or combined with stock to make veloute. Today the term has been broadened to include soups that incorporate cream, but do not necessarily begin with a roux. To further expand on the modern definition, many cream soups incorporate sour cream, cream fraiche, or yogurt.
How to Make a Roux
Roux is made by combining some type of fat (typically butter) with flour in equal parts by weight. The fat is warmed over medium heat and then the flour is added to it all at once. The roux is then cooked while being stirred constantly for about 5-8 minutes. The consistency of a proper roux should resemble very wet sand. Depending on how the roux is being used, it is sometimes cooked for an additional amount of time until it is blonde or even brown in color. For the purpose of cream soups, however, a white roux is almost always used.
The Scoop on Bechamel
Bechamel has many different applications and derivatives in classical cooking. It is made by slowly whisking warm milk into roux until no lumps remain and then simmering to ensure that the taste of raw flour is totally cooked out. The top of the bechamel is skimmed as needed to remove any impurities that rise to the surface as it cooks. It is crucial to keep an eye on bechamel and stir often to prevent it from scorching. After the proper cooking time, the bechamel is seasoned with salt and white pepper (black pepper would leave noticeable flecks in the white sauce) and strained through cheesecloth. Depending on its use, the bechamel can then be flavored with any number of herbs, spices, and other flavorings. A correct bechamel should be silky with no graininess and should have a nice sheen.
About Classic Veloutes
Veloute is basically the same as bechamel, however white stock is used in the place of milk. The stock is generally made from chicken, veal, or fish depending on how the veloute will be used. When used as a soup base, veloutes are classically finished with cream and sometimes egg yolks.