In a large pot over medium heat, heat 2 T olive oil. Add the celery, carrot and onion; saute until the vegetables have begun to soften 7-10 minutes. Add the garlic and cook for an additional 1-2 minutes.

Add all the stock and the meatballs. Bring to a simmer and continue to cook until the meatballs have thawed and warmed through, about 15 minutes.

Add the pasta and simmer until al dente, approximately 10 minutes. Stir in the spinach until wilted.

Ladle into bowls and serve.