Throw all the ingredients for bechamel in at once and 10 minutes later you have perfectly velvety sauce.
1796, from French béchamel, named for Louis XIV's steward, Louis de Béchamel, marquis de Nointel (1630-1703), who perfected it. Gamillscheg identifies him as a great gourmet of the time ("eines bekannten Feinschmeckers des 17. Jhdts.").