Saute the veal and mushrooms in 2 tablespoons butter, remove the mixture to a bowl, and add one of the beaten eggs, the garlic, parsley, salt and pepper. Lay the chicken breasts flat, pound them thin with a rolling pin or other blunt instrument, and stuff each piece with some of the veal mixture. Fold them up securely and fasten the rolled breasts with toothpicks. Dip each piece first in the remaining egg, then in flour, then the breadcrumbs. Refrigerate the breaded breasts for at least an hour (this helps to keep the breading on when they are fried). Heat the remaining 2 tablespoons of butter, then fry the breasts over medium heat until well browned all over. Cover the skillet when they are brown and cook a little longer. When done, remove to a hot platter and remove the toothpicks. Rinse the pan with the broth, scraping it, and pour sauce over the chicken.