In a large mixing bowl, combine ground beef, bread crumbs, Parmesan cheese, egg, minced garlic, Italian seasoning, salt, and pepper. Mix thoroughly until just combined.

Heat olive oil in a Dutch oven over medium-high heat. Add meatballs in batches and brown for 5-7 minutes, turning occasionally.

In the same pot, add more olive oil if needed, then toss in the diced onion, carrots, and celery. Sauté for about 5 minutes until the onions are translucent.

Stir in beef broth, diced tomatoes, tomato paste, and paprika. Bring to a boil, then reduce heat to low and let simmer for about 10 minutes.

Return browned meatballs back to the pot and let simmer for 30 minutes on low heat.

Add pasta, stirring gently. Simmer for another 10-12 minutes until pasta is tender.

Stir in fresh spinach and let cook for 2-3 minutes until wilted.

Remove from heat, stir in parsley, and adjust seasoning before serving.

Ladle into bowls and garnish with grated Parmesan cheese, if desired.