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 until serving.
02 - In a medium bowl, combine ground chicken or turkey, Parmesan, breadcrumbs, egg, minced garlic, parsley, salt, and pepper. Mix gently until just combined—avoid overworking for tender results.
03 - Shape mixture into ¾-inch balls, approximately 28-32 pieces. Keep hands lightly moistened to prevent sticking.
04 - Heat olive oil in a large pot over medium heat. Add meatballs in batches without overcrowding. Brown lightly for 3-4 minutes, turning occasionally. Remove to a plate—interior will finish cooking in soup.
05 - In the same pot, add diced onion and garlic. Sauté for 2 minutes until softened and fragrant. Add zucchini, carrot, and cherry tomatoes; cook for 3 minutes until vegetables begin to soften.
06 - Pour in broth and bring to a gentle boil. Add pasta and return browned meatballs to pot. Reduce heat and simmer for 8-10 minutes until meatballs are cooked through and pasta is al dente.
07 - Stir in baby spinach and cook for 1-2 minutes until just wilted. Taste and adjust seasoning with salt and pepper as needed.
08 - Ladle hot soup into serving bowls. Swirl a generous spoonful of reserved pesto into each portion immediately before serving.