In a large bowl stir together well the wine, vinegar, 1 cup water, 3 of the onions, quartered, celery leaves, salt, sugar, mustard seeds, nutmeg, cloves, peppercorns, parsley, and bay leaves. Add the meat and let it marinate, covered and chilled, turning occasionally, for 3 to 4 days.
Remove the meat from the marinade and reserve the marinade. Season the meat with salt and pepper. In a kettle heat the clarified butter over moderately high heat until it is hot but not smoking. Add the meat and brown on all sides. Add the reserved marinade and gently simmer the mixture, covered, for 3 1/2 to 4 hours, or until the meat is tender.
Transfer the meat to a cutting board. Strain the cooking liquid and skim off the fat. Transfer 1/2 cup of the cooking liquid to a saucepan, bring to a boil, and stir in the gingersnaps and the remaining liquid, a little at a time, stirring. Boil the sauce, stirring, until it is thickened and add salt and pepper to taste. Slice the meat and serve it with the sauce and potato dumplings.
Recipe courtesy of Gourmet Magazine