In a bowl combine well the veal, 2 tablespoons of the Parmesan, the parsley, the bread crumbs, the salt, half the egg, reserving the remaining egg for another use, and freshly ground pepper to taste and form the mixture into 12 walnut-size balls. (The mixture will be soft.) In a large heavy saucepan heat 1 tablespoon of the oil over moderately high heat until it hot but not smoking, in it saute the meatballs, turning them, for 3 minutes, or until they are just firm to the touch and browned lightly, and transfer them with a slotted spoon to a plate. Add the remaining 2 tablespoons oil and the onions to the pan and cook the mixture over moderately low heat, stirring occasionally, until the onion is softened. Add the garlic and cook the mixture, stirring occasionally, for 2 minutes. Add the escarole and cook the mixture, cover, over low heat, stirring occasionally, for 3 minutes, or until the escarole is wilted. Add the broth, the meatballs, and freshly ground pepper to taste, bring the liquid to a boil, and simmer the soup for 3 minutes. Serve the escarole soup sprinkled with the remaining 3 tablespoons Parmesan.