In a medium bowl, combine the pine nuts, currants, pecorino, prosciutto, parsley, garlic, and salt and pepper to taste. Add the egg and mix well to blend. Divide mixture into 12 equal portions. Spread the mixture onto 1 side of each of the 12 veal pieces, leaving a 1/2-inch perimeter uncovered on each. Roll each piece of veal tightly and bind with butcher's twine to ensure that filling stays intact. Season the veal with salt and pepper.
In a large casserole or Dutch oven, heat the olive oil until almost smoking. Sear the veal rolls, remove when brown. Add the onion and saute 2 minutes. Add the pancetta, tomatoes and wine and bring to a boil, scraping the bottom of the pan to loosen the browned bits. Reduce to a simmer and add the veal. Cover tightly and allow to braise for 1 hour. Allow to rest 30 minutes before serving with sauce.
Recipe copyright 2000, Mario Batali. All Rights Reserved.