Prepare the Meatballs:
In a large mixing bowl, combine the ground meat, Parmesan, breadcrumbs, egg, garlic, parsley, salt, and pepper. Mix until just combined; avoid overmixing. Roll the mixture into small meatballs (about 1 inch in diameter) and place them on a parchment-lined baking sheet.
Cook the Meatballs:
Preheat the oven to 400°F (200°C) and bake the meatballs for 10-12 minutes, or until lightly browned and cooked through. Alternatively, you can brown them in a skillet over medium heat.
Sauté the Vegetables:
In a large pot or Dutch oven, heat the olive oil over medium heat. Add the diced onion, carrots, and celery. Sauté for 5-7 minutes until softened and fragrant.
Build the Soup Base:
Pour the chicken broth into the pot and bring to a gentle simmer. Season with salt and pepper to taste. Add the baked meatballs and let them simmer in the broth for 10 minutes to enhance the flavor.
Cook the Pasta:
Stir in the small pasta and cook according to the package instructions, typically about 8-10 minutes, until tender.
Add the Greens:
Stir in the chopped spinach (or your preferred greens) and cook for 2-3 minutes until wilted.
Serve:
Ladle the soup into bowls and garnish with grated Parmesan cheese. Serve hot with crusty bread or garlic toast on the side.