3 tablespoon butter
1 teaspoon flour.
1/4 cup vinegar
1/4 cup beef broth
1/4 cup prepared horseradish mustard
3 tablespoon brown sugar.
1 slightly beaten egg yolk.
Melt butter; blend in flour. Add vinegar, beef broth, prepared horseradish mustard, and brown sugar. Cook slowly, stirring constantly, till thick. Gradually add a little hot mixture to 1 slightly beaten egg yolk. Return to hot mixture. Bring sauce to boiling, stirring constantly. Serve hot with corned beef or ham.
Makes 1 cup.