Optional: adding a pound of ground beef or Italian sausage is fantastic with this recipe! Cook the meat on the saute function with a little salt and pepper, drain the grease, and proceed with the recipe (just make sure when you add the broth to scrape the bottom of the pot really well before adding the other ingredients).
Lighten it Up: If you want to lighten up the cream a bit, I've had great success making this with 1 cup milk + 1 tablespoon cornstarch (whisked together) + 1 cup cream. I haven't tried subbing all the cream for a milk + cornstarch mixture, but you could experiment!
For an Extra Saucy Pasta: add 1/4 to 1/2 cup extra broth, cream or crushed tomatoes. Any variety of tube pasta will work great here! When I can't find ziti, I've used penne or rigatoni. Also, I've subbed in a 15-ounce can diced tomatoes blended with 2 tablespoons tomato paste for the crushed tomatoes with great results.