Place the stock in a saucepan, over medium heat. Bring to a boil. In a small mixing bowl, combine the eggs and pecorino cheese. Season with pepper and mix well. Whisk the mixture into the boiling stock. Cook for 1 minute. Add the mozzarella cheese and parsley. Whisk well. Place 2 pieces of the bread into each shallow bowl. Ladle the soup over the bread and serve.
Yield: 6 servings