In a large, non metal bowl, combine red wine vinegar, red wine, onions, carrots, bay leaf, whole allspice, whole cloves, peppercorns, and salt.

Place roast in marinade, cover and refrigerate 3 days, turning once daily.

Remove roast from marinade and wipe dry

In a large sauce pan, heat the marinade over medium low heat.

Melt 1/4 cup butter with the oil in a dutch oven with the roast

Brown the beef on all sides, sprinkling the flour over it as you turn it.

Pour marinade off from the meat, skim the fat, and strain.

In a large skillet, over low heat, melt the remaining 1/4 cup butter with sugar.

Cook and stir until golden in color

Pour in strained marinade slowly, stirring until smooth and thickened.

Sprinkle in the gingersnaps