In a large mixing bowl, add the ground beef, Panko breadcrumbs, Parmesan cheese, milk, beaten egg, 2 cloves of minced garlic, 1 tsp dried oregano, salt, and pepper.

Gently mix with your hands until just combined. Be careful not to overmix, as this can make the meatballs tough. Roll the mixture into uniform, 1-inch meatballs (this should yield about 24-28).

Cook the meatballs using one of the following methods: Air Fryer Method (Recommended): Arrange the meatballs in a single layer in the air fryer basket. Cook at 400°F (200°C) for 8-10 minutes, until browned and cooked through. Skillet Method: Heat 1 tbsp of olive oil in a large skillet over medium-high heat. Add the meatballs in a single layer (work in batches if necessary) and brown on all sides, about 5-7 minutes total. They do not need to be fully cooked inside. Set the browned meatballs aside.

In a large pot or Dutch oven, heat 1 tbsp of olive oil over medium heat. Add the chopped onion, carrots, and celery. Sauté for 5-7 minutes, stirring occasionally, until the vegetables have softened.

Add the 3 cloves of minced garlic and cook for 1 minute more, until fragrant.

Pour in the crushed tomatoes, beef broth, 1 tsp dried oregano, dried basil, and the bay leaf. Season with a pinch of salt and pepper. Stir everything together.

Bring the soup to a boil, then reduce the heat to low, cover, and let it simmer for at least 15 minutes to allow the flavors to meld.

Stir in the uncooked small pasta and the cooked meatballs. Increase heat to maintain a gentle simmer and cook for 10-12 minutes, or until the pasta is al dente and the meatballs are heated through.

Remove the pot from the heat and discard the bay leaf. Stir in the fresh spinach until it wilts, which should only take about 1-2 minutes.

Taste the soup and adjust the seasoning with more salt and pepper if needed. Ladle into bowls and serve hot, garnished with fresh parsley and extra grated Parmesan cheese.