White Sauce

Ingredients

 * 1 part butter
 * 1 part flour
 * fish stock (to desired thickness)

Directions

 * 1) In a saucepan, melt equal parts of butter and flour (over low heat), whisk them together (do not let the mixture get brown) until you obtain a homogeneous paste.
 * 2) Let it cool for a few minutes then gradually add some hot fish stock, whisk continuously to prevent lumps.
 * 3) Bring the mixture slowly to boil and let simmer for 15 to 20 minutes.