Spicy Buffalo Sauerbraten with Gingersnap Sauce - serves 6

4 pounds boned, rolled, and tied Buffalo rump roast
1 tbsp vegetable oil
6 tbsp butter or margarine
2-1/2 tbsp all-purpose flour
2 tbsp sugar
5 to 7 crushed gingersnaps
2 tbsp light molasses
1/2 cup raisins
Marinade:
1 tsp ground black pepper
2 medium onions, sliced
1 medium carrot, sliced
1 celery stalk, chopped
2 bay leaves
4 whole cloves
8 whole allspice
1 tsp dry mustard
1/2 tsp celery seed
1/2 tsp dried thyme
1/2 tsp mace
2 cups red wine vinegar

In a medium bowl, combine the marinade ingredients. Place the meat in a 2-gallon plastic bag and pour the marinade over the roast. Close the bag tightly and place in a flat glass dish. Refrigerate for 4 days, turning occasionally.
Preheat the oven to 300ºF. Remove the meat from the bag, reserving the marinade. In a large roasting pan, heat the oil and 1 tablespoon of the butter or margarine over medium heat. Add the meat and brown on all sides, about 15 minutes. Pour the reserved marinade over the browned roast, cover, and bake for 4 hours.
Remove the meat to a heated platter. In a large saucepan, melt the remaining 5 tablespoons of butter or margarine. Add the flour and cook until the mixture bubbles, then pour in the pan juices and whisk until smooth.
Stir the sugar, gingersnaps, molasses, and raisins into the sauce; cook and stir until blended-the sauce will be fairly thick. Carve the meat into thick slices and serve with the sauce.