In a large bowl, combine the ground turkey, breadcrumbs, egg, minced garlic, parsley, Italian seasoning, salt, and pepper. Mix until just combined; don’t overmix or your meatballs will be tough!

Roll the mixture into small, bite-sized balls—about 1 inch in diameter. Set these aside while you prepare the soup.

In a large pot, heat the olive oil over medium heat. Add the chopped onion, carrots, and celery, cooking until the vegetables begin to soften, about 5-7 minutes.

Stir in the minced garlic and let it cook for about 1 minute, being careful not to let it brown.

Pour in the broth and add the diced tomatoes, letting everything come to a gentle boil.

Carefully drop the meatballs into the pot. Turn the heat down to low and let the soup simmer gently for about 20 minutes.

Stir in the fresh spinach or kale just a few minutes before serving until wilted. Adjust the seasoning with salt and pepper as needed.