Prosciutto should be thinly sliced and cut into julienne strips. Veal shoulder should be like scaloppine, pounded In a small bowl, mix the hot wine, broth and tomato paste until the paste dissolves. Set aside and keep warm. Spread the veal slices on a flat surface, then cover each with pepper, cheese and prosciutto. Roll up each slice and secure with large toothpicks. Set aside. In a large skillet, saute the onion in oil and butter over medium heat, then add the carrots and celery. Cook for 10 minutes, or until the carrots and celery are soft. Add the veal roll to this mixture and saute on all sides for a few minutes until the meat is golden brown. Next add the broth, wine and tomato paste mixture, roll the veal in it until thoroughly coated and continue cooking until the sauce thickens. Serve immediately.