Yield: 10 Servings
| Measure | Ingredient |
|---|---|
| 4 pounds | Rump Roast; Beef, Boneless |
| 2 \N | Onions; Thinly Sliced |
| 8 \N | Peppercorns |
| 4 \N | Cloves; Whole |
| 1 \N | Bay Leaf |
| 1 cup | White Vinegar; Mild |
| 1 cup | Water |
| ½ cup | Cider Vinegar |
| ¼ cup | Vegetable Oil |
| ½ teaspoon | Salt |
| 2 cups | Water; boiling |
| 10 \N | Gingersnaps |
| ½ cup | Sour Cream |
| 1 tablespoon | Unbleached Flour |
Place the beef roast in a deep ceramic or glass bowl. Add onions, peppercorns, cloves, and bay leaf. Pour white vinegar and cider vinegar over the meat; chill, covered, for 4 days. Turn meat twice each day. Remove the meat from the marinade, dry it well with paper towels, and strain the marinade into a bowl. Reserve onions and 1 cup marinade. In a Dutch oven brown the meat on all sides in hot vegetable oil. Sprinkle meat with salt. Pour boiling water around the meat. sprinkle in crushed gingersnaps, and simmer covered for 1½ hours. Turn often. Add 1 cup of reserved marinade and cook meat 2 hours or more, until tender. Remove the meat and keep it warm.
Strain the cooking juices into a large saucepan. In a small bowl mix sour cream with flour. Stir it into the cooking juices and cook, stirring, until sauce is thickened and smooth. Slice meat in ¼ inch slices; add to hot gravy. Arrange meat on a heated plater and pour extra sauce over it.