Preheat oven to 325 degrees. In a Dutch oven or deep skillet, heat oil over medium heat. Add meat and brown on all sides. Transfer to a plate lined with paper towels and drain off all the fat in the pan. Return the pan to the heat and immediately add brandy, stirring to scrape up any browned bits of meat in the bottom. Cook until the brandy is reduced to a syrupy glaze. Stir in stock, mustards, shallots, sun-dried tomatoes, garlic, juniper berries and bay leaf and bring to a boil. Return the meat to the pan, cover tightly and place in the oven. Bake, turning the meat every 30 minutes, for 1 1/2 to 2 hours, or until very tender. Remove bay leaf and season the sauce with pepper. Cut the meat into thin slices, arrange on platter, and spoon the sauce over top.