In a mixing bowl, combine ground chicken, gluten-free breadcrumbs, grated parmesan, egg, minced garlic, finely chopped onion, salt, and pepper. Gently mix until just combined, then shape into 1-inch meatballs.

Heat a tablespoon of olive oil in a large pot over medium heat. Add the meatballs in batches and sear for about 4-5 minutes until nicely browned. Remove and set aside.

In the same pot, add additional olive oil if needed, then sauté chopped onion, diced carrots, and sliced celery over medium heat for 5-7 minutes until tender.

Pour in chicken broth and water, bringing to a simmer while scraping the pot bottom. Once simmering, continue to the next step.

Add small pasta, cooking for about 8-10 minutes until tender yet al dente.

Return the browned meatballs to the pot with any released juices. Stir gently and add fresh spinach, allowing to wilt for 2-3 minutes.

Taste and adjust seasoning. Ladle into warm bowls and serve immediately.