Cumberland Sauce - cooking recipe

Ingredients

1 (12 oz.) jar currant jelly
1 egg yolk
2 Tbsp. sugar
1/4 c. raisins
3/4 tsp. dry mustard
2 Tbsp. vinegar
salt and pepper

Preparation

Melt the jelly in the top of a double boiler.
Beat in all the other ingredients except the raisins and stir until the sauce is thickened.
Do not despair if this is slow work; it may take as much as 15 minutes.
I find I can read a book while I am stirring. When the sauce has thickened, stir in the raisins.