In a large pot brown the two pounds of Italian sausage over medium heat, retain the grease and add the onion and garlic. Cook until the onions are translucent. Drain any excess grease. Next add the crushed tomatoes, the chicken broth, the frozen spinach and the Italian seasoning, plus the garlic salt. Let the soup simmer for about ten minutes, next, add in the tortellini and let it cook for 5-10 more minutes. Longer is good too, but if you are in a rush that time will cook the tortellini. Serve and top with grated parmesan. Enjoy!