Combine beans, onion, chili peppers, corn, tomato sauce, cumin, chili powder and taco seasoning in a slow cooker. Place chicken on top and cover. Cook on low for 10 hours or on high for 6 hours. Half hour before serving, remove chicken and shred. Return chicken to slow cooker and stir in. Top with fresh cilantro. Also try it with low fat cheese and sour cream.