If you want to skip the instructions to brown the meatballs, just drop them off a long-handled spoon directly into the simmering stock.
To make the meatballs in advance, set the rolled meatballs on a rimmed baking sheet and freeze until firm. Then drop the meatballs into a plastic freezer bag. Defrost them overnight in the refrigerator before cooking.
INGREDIENTS
For the meatballs:
2 slices white bread or 1 soft dinner roll (about 3-inches across), left out overnight
1/4 cup whole or reduced-fat milk (60 ml)
1 large egg
1/4 cup grated Parmesan cheese (32 g)
1 pound ground turkey, preferably dark meat or at least 85% lean
1 teaspoon salt
1/2 teaspoon black pepper
2 tablespoons chopped fresh parsley
2 tablespoons olive oil
For the soup:
2 tablespoons olive oil
2 stalks celery, halved lengthwise and thinly sliced
3 medium carrots, thinly sliced
1/2 teaspoon salt
1/4 teaspoon ground pepper
8 cups chicken stock (2000 ml)
1/2 cup orzo pasta (70 g)
5 ounces baby spinach, with any long stems removed (165 g, or 8 loosely packed cups)
1 cup grated Parmesan (128 g), for serving
DIRECTIONS
1 Make the meatball mixture: Shred the bread or roll with your fingers into 1/2-inch pieces. In a bowl, combine the bread or roll, milk, egg, Parmesan, turkey, salt, pepper, and parsley. With a clean hand, work the mixture until it is well blended.
2 Shape meatballs: With wet hands, shape 2 teaspoons of the mixture into a small walnut-sized meatball (1 1/2-inches across). Repeat, making 30 to 34 meatballs total.
3 Brown the meatballs (optional): In a nonstick skillet over medium heat, heat 1 tablespoon of the olive oil. When it is hot, add half the meatballs and cook for 3 minutes, or until they are browned on the bottom. Turn and cook 2 minutes more, until browned on the other side. Remove from the pan. (The meatballs will not be cooked through.)
Cook the remaining meatballs in the remaining 1 tablespoon olive oil in the same way.
4 Make the soup: In a soup pot, heat the oil. Add the celery, carrots, salt, and pepper. Cook, stirring often, for 8 minutes. Add the stock and bring to a boil. Add the meatballs and orzo. Return the soup to a boil, lower the heat, and cover the pan.
Simmer for 15 minutes, stirring occasionally, or until the meatballs are cooked through and the orzo is tender (cut the meatballs in half to check them; taste the orzo).
5 Cook the spinach: Add the spinach to the soup and cook 2 minutes more, or just until it wilts.
6 Serve the soup: Taste the soup for seasoning and add more salt and pepper, if you like. Ladle into bowls and sprinkle with Parmesan.