White chicken chili is a very contemporary creation, designed to lighten up the beefy original. Like a lot of chili fans (like me) you may not immediately embrace the idea, at least until you taste this version. Using cooked chopped chicken, rather than ground, and making sure the finished dish is properly thick and spicy results in a chili that truly sticks to the ribs and satisfies. And, if it doesn't sound too un-chili-like, this white and green ragout, with its large, pinkish-tan beans, is actually pretty. Serve the chili with corn tortillas and chilled Mexican beer, for a great cold weather supper.