01 -
Put a rack in the middle of your oven and heat it to 400°F (200°C). Cover a baking sheet with foil and spray it with cooking spray, or just use parchment paper instead. This way your meatballs won't stick and you'll have less mess to clean up.
02 -
Grab a medium bowl and mix up all the meatball stuff except the chicken: the breadcrumbs, Parmesan, egg, dried parsley, pesto, garlic powder, and poultry seasoning. Stir it all with a fork until it's mixed well. Then add your ground chicken and gently mix until it's all combined—don't mix too much or your meatballs will end up tough. Scoop out tablespoon-sized portions to make your meatballs (you'll get about 28-35 of them). Put them on your baking sheet with about an inch between each one. Bake them for 18-22 minutes, until they're fully cooked and reach 165°F inside.
03 -
While your meatballs are in the oven, let's make the soup. Warm up a big pot or Dutch oven (at least 5-quarts) over medium heat. Pour in the olive oil, and when it's hot, toss in your chopped onions. Cook them for about 5 minutes until they look clear and soft. Throw in a pinch of red pepper flakes and stir for half a minute until you can smell them. Now pour in your chicken stock and water, and drop in those Parmesan rinds. Let everything bubble gently for 15 minutes so the rinds can give their flavor to the broth.
04 -
After the broth has bubbled for 15 minutes, dump in the pasta and cook it for as long as the package says. When the pasta is almost done but still a bit firm, stir in the pesto and greens. Let the greens wilt down. Drop in your baked meatballs and let everything simmer together for the last 3 minutes until the pasta is just right and the meatballs are warmed through. Find those Parmesan rinds with tongs or a slotted spoon and take them out.
05 -
Try the soup and add more seasonings if you need to, but remember the Parmesan and pesto already make it pretty flavorful. Scoop the hot soup into bowls, making sure everyone gets plenty of meatballs, pasta, and greens. Sprinkle some extra Parmesan on top if you want. Serve it right away while it's hot, maybe with some crusty bread on the side.