- In a small saucepan, pour milk. Stud onion with cloves and add to milk. Simmer over low heat for about 5 minutes.
- Meanwhile, in another small saucepan, prepare roux (a cooked mixture of flour and butter). With a whisk, cook flour with butter until melted and just blond.
- Remove onion from milk. Pour hot milk into roux and cook, whisking constantly until mixture thickens. Adjust seasoning with salt and pepper (use white pepper for a white béchamel). Add a pinch of nutmeg, if desired.