Pour 1 cup half-and-half into a small saucepan; cook over low heat, stirring occasionally, until bubbly. Combine next 5 ingredients with remaining half-and-half, mixing well; gradually add to heated half-and-half, mix well. Cook over low heat, stirring constantly, until thickened and smooth.
Remove sauce from heat, and gradually stir in vinegar. Serve hot.
Oxmoor House Homestyle Recipes