Heat olive oil in a large pot over medium heat. Add diced onions, carrots, celery, and garlic and saute for about 5-7 minutes or until onions are translucent.
Add chicken broth, bay leaf, and parmesan rind, and bring to simmer.
Gently add in your meatballs. Cover and let cook for about 30 minutes.
Next, add in the chopped kale and your pasta, and cook for another 7-10 minutes, depending on how long your pasta needs to cook.
Add salt and pepper to taste and serve with freshly grated parmesan cheese.