James' Bechamel Sauce
Equal parts plain flour[1] & butter (ie 1 heaped spoon each)
Milk
Fry both in a saucepan to form a "blonde roux" ie colour loses yellowness & starts to bubble
VERY slowly add small amounts of milk while stirring until it becomes liquid.
Can add milk faster then. Continue until you have sauce to the amount and consistency you want.
Lea