Place a large pot or dutch oven over med-high heat and add the sausage, breaking it up in to small pieces with a fork as it browns. Continue cooking until the sausage is no longer pink. Transfer the sausage to a bowl with a slotted spoon and discard all but 1 tablespoon of fat.Return the pot to the stove and add the onions. Cook the onions until translucent, approximately 4-5 minutes. Add the garlic, cooking for one minute until fragrant.Stir in the Italian seasoning and 1/4 cup of chicken stock to deglaze the pan being sure to scrape up any brown bits with a wooden spoon.Stir in the tomatoes, beans, sausage and remaining stock. Add the pasta and bring the soup to a boil. Cook for 6-7 minute or until the pasta is al dente.Stir in the spinach. Serve immediately topped with parmesan cheese.