Preheat your oven to 400°F (200°C).
In a mixing bowl, combine ground beef, breadcrumbs, Parmesan cheese, parsley, egg, minced garlic, salt, and pepper. Mix well and form into small meatballs, about 1 inch in diameter.
Place the meatballs on a baking sheet and bake in the preheated oven for about 15 minutes, until browned.
In a large pot over medium heat, add the onion, carrots, and celery. Sauté for about 5 minutes, until the vegetables are softened.
Pour in the chicken broth and add Italian seasoning. Bring to a gentle boil.
Add the small pasta to the soup and cook according to the package instructions, typically about 7-10 minutes.
Once the pasta is cooked, add the baked meatballs and chopped greens to the pot. Stir and let them simmer for another 5 minutes.
Taste the soup and adjust seasoning with salt and pepper as needed.
Serve hot with additional grated Parmesan cheese if desired.