Melt the butter in a pan over medium heat.

Whisk in the flour.

Pour in all the milk, whisking constantly until it starts to boil.

Season with salt, lower the heat, cover and simmer gently, stirring occasionally, for at least 20 minutes.

Bechamel sauce should not taste floury.

Remove the pan from the heat

Taste and add more salt if neccesary and season with pepper and nutmeg.

If the sauce is too thick, add a little more of milk.

If too runny, return to the heat and a pat of butter mixed with an equal quantity of all-purpose flour.

Makin this delicious sauce, considered a basic sauce because of the numerous variations to which it has given rise, is an essential skill for anyone keen to cook.