Heat a stockpot to medium high. Once hot, add olive oil, carrots, celery and onion. Saute until vegetables begin to soften.
Next, add sausage, breaking it apart with wooden spoon.Cook, stirring until sausage is cooked through.
Remove pot from heat and add minced garlic. Stir for 30 seconds.
Return to heat and add roasted tomatoes, navy beans and chicken broth.
Bring to a boil and turn down to simmer for about 15 minutes.
Just before serving, add zucchini and cook about 5 minutes.
Add salt and pepper, taste and adjust seasonings.
Serve with ribbons of fresh basil and Pecorino Romano cheese if tolerated.
This soup freezes well.
Recipe by my BIG FAT grain free life at http://mybigfatgrainfreelife.com/2011/12/white-bean-soup-with-chicken-sausage-roasted-tomatoes-and-zucchini.html