½ cup rich chicken stock

½ cup vinegar

Yolks 5 eggs

2 tablespoons mixed mustard

1 teaspoon salt

¼ teaspoon pepper

Few grains cayenne

½ cup thick cream

⅓ cup melted butter

Reduce stock in which a fowl has been cooked to one-half cupful. Add vinegar, yolks of eggs slightly beaten, mustard, salt, pepper, and cayenne. Cook over boiling water, stirring constantly until mixture thickens. Strain, add cream and melted butter, then cool.