Cheddar Cheese Sauce

heat butter in a large skillet, over a low flame add the flour and whisk to make a white roux remove from heat and allow to cool slightly scald the milk in a saucepan, over a medium flame gradually beat the scalded milk into the roux place over a moderate flame heat and stir to a boil, reduce heat to a simmer impale the bay leaf to the onion with the clove add to the sauce simmer for 15-30 minutes, stirring often add grated cheese, dry mustard, and worcestershire sauce stir until cheese melts add hot milk as needed to adjust the consistency season very lightly with salt, nutmeg, and white pepper strain through a chinois top with melted butter to keep a skin from forming keep warm in a bain marie or cool quickly in ice or a vented water bath and chill serve hot or warm