01 - Combine basil, Parmesan, pine nuts, garlic, and salt in a food processor. Pulse until finely chopped. With motor running, drizzle in olive oil until smooth and creamy. Set aside for serving.
02 - Mix ground chicken or turkey, Parmesan, breadcrumbs, egg, garlic, parsley, salt, and pepper until just combined. Shape into ¾-inch mini balls, yielding approximately 28-32 meatballs.
03 - Heat olive oil in a large pot over medium heat. Add meatballs in batches and brown lightly for 3-4 minutes. Remove to a plate—meatballs will finish cooking in the soup.
04 - In the same pot, add onion and garlic. Sauté for 2 minutes until softened and fragrant. Add zucchini, carrot, and cherry tomatoes; cook for another 3 minutes until vegetables begin to soften.
05 - Pour in broth and bring to a gentle boil. Add pasta and return browned meatballs to pot. Simmer for 8-10 minutes until meatballs are cooked through and pasta is tender.
06 - Stir in baby spinach and cook for 1-2 minutes until just wilted. Taste and adjust seasoning with salt and pepper as needed.
07 - Ladle hot soup into bowls. Swirl a generous spoonful of fresh pesto into each bowl immediately before serving.