How To Make A Basic Cheese Sauce

or 1/4 cup or 50 g butter

or 50 g All Purpose Flour

or 550 ml milk

or 150 g grated cheddar cheese OR 8oz / 225 g cooked onions (OR 8 oz / 100 g chopped shrimps.)

yellow or grained mustard.

your favourite dried or fresh herbs. I used Tarragon. Parsley is also very nice.

salt. I did not add much as my cheese was a little salty.