Using a large kettle, I used a 6 quart Le Creuset stockpot, saute sausage until browned and breaking up into coarse pieces.Add chopped onion and celery and saute about 6-8 minutes until they begin to get tender.Add beef stock and basil. Bring to a gentle simmer.Add tomatoes and rice and simmer until rice is tender...about 20 minutes, while stirring occasionally.Add spinach and cook a few more minutes until spinach is wilted. Add salt and pepper to taste.Garnish each bowl with cheese before serving.