Add the ricotta, 2 cups mozzarella, parmesan, egg, parsley, and pepper to a large bowl. Stir to combine. Refrigerate until ready to stuff the pasta tubes.
Bake for 35-45 minutes until bubbly around the edges. Uncover and cook 5 minutes. Garnish with chopped parsley, if desired. Rest for 15-20 minutes before serving.