Brown the sausage in a large soup pot set over medium heat. Transfer to a plate with a slotted spoon, leaving any grease behind. Add the onion and garlic and cook 2 minutes, or until soft. Add the carrot and celery and cook 5 minutes. Stir in the Italian seasoning.

Pour in the chicken stock. Add the diced sweet potato and the browned sausage. Bring to a boil, then reduce to a simmer. Cook for 30 minutes.

Add the kale, white beans, and quinoa. Simmer another 20 minutes, or until the quinoa and sweet potato are cooked through. Season to taste with salt and pepper.

Serve topped with parmesan cheese, if desired.