If using flavorings, add these to the milk. Bring the milk to a boil in a saucepan, cover and leave to infuse for 10 minutes. For plain béchamel, simply bring the milk to a boil without adding any flavorings.
To make the roux, melt the butter in a heavy saucepan. Whisk in the flour and cook until foaming, about 1 minute. Remove the pan from the heat and let it