In a large bowl, combine the veal, duck liver, chopped pancetta, bread crumbs, garlic, rosemary, and thyme, season with salt and pepper, and mix well. Set aside.
Preheat the oven to 375 degrees F.
Season the duck inside and out with salt and pepper and stuff the cavity with the mixture, wrap the duck with the sliced pancetta, and truss the duck with butcher's twine.
In a dutch oven, heat the olive oil over medium-high heat, add the onion, carrot, and celery, and cook until softened and golden brown. Add the duck and sear on all sides. Place the duck in the oven, cook for 10 minutes, then cover with the white wine.
Cook in the oven until the duck is sizzling and the stuffing is completely cooked through, about 1 hour. Serve hot.
Recipe copyright Mario Batali, 2002. All Rights Reserved