1. Preheat oven to 375°F (190°C). Line a baking sheet with parchment paper.
2. In a bowl, mix ground chicken, breadcrumbs, Parmesan, egg, garlic, salt, and pepper. Form into small meatballs and place on the baking sheet.
3. Bake meatballs for 15 minutes or until cooked through.
4. In a large pot, heat olive oil over medium heat. Add onion and garlic, cook until softened.
5. Add chicken broth, carrot, and celery. Bring to a boil, then reduce heat and simmer for 10 minutes.
6. Add meatballs, spinach, and pasta to the pot. Cook until pasta is tender. Season with salt and pepper to taste.