Put all ingredients except cheese in a saucepan (you may also want to leave out part of the onion if you desire to garnish the chili with fresh onion when done).  Heat on medium until the chicken is thoroughly cooked, then lower heat and let simmer until you're ready to eat (I let mine simmer for about 20 minutes in order to let the flavor soak in).  Garnish with cheese and fresh onions if desired.  Voila.  The best chili I've ever had!