This is a really quick and easy sauce to add to fish and gives it the finishing touch with the lemon giving a bit of a zing. There is enough sauce in this recipe to be able to also use it over hot vegetables if you like.
Melt Butter in a small saucepan. mix the flour with a small amount of milk once its a smooth paste add the remaining milk stir well and add i to the saucepan stirring constantly until the sauce thickens.
Remove from heat then add the lemon juice, parsley and seasoning and serve.