Mustard Sauce - cooking recipe

Ingredients

1/2 c. dry mustard
1/2 c. white vinegar
1/4 c. sugar
1 egg yolk

Preparation

Combine mustard and vinegar in a small bowl.
Cover and let stand at room temperature.
Mix sugar and egg yolk in a small saucepan.
Add mustard and vinegar.
Mix and cook over low heat, stirring constantly until slightly thickened.
Cover and chill. Serve at room temperature.