Pour the dry Great Northern beans into the base of a 6 quart slow cooker with the chicken broth, carrots, celery, onion, butternut squash, garlic, bay leaves, thyme, kosher salt and freshly ground black pepper. Stir gently to combine all the ingredients.
Cook on low for 8 hours. Meanwhile, form the Italian sausage into small meatballs and refrigerate until ready to cook.
Take ½ cup of the soup broth and pour into a small bowl. Whisk in the tomato paste until smooth and then add back to the slow cooker.
Add the baby kale and then the sausage meatballs and cook for an additional 30 to 45 minutes or until the sausage is cooked through and the beans are tender.
Adjust seasonings to taste and serve with shaved Parmesan cheese scattered on top.