Doc's Chili (Biggest Loser)

1 1/4 lbs ground turkey or turkey sausage
3 c. chopped yellow onion
3 c. diced tomatoes (28 oz)
1 1/2 c. pinto beans (15 oz)
1 1/2 c. black beans (15 oz)
1 1/2 c. chicken broth
2 Tbsp chopped garlic
2 Tbsp chili powder
1 Tbsp chopped fresh oregano
(or 1 tsp dried oregano)
1 tsp ground cumin
1 tsp mustard powder