1. Put chicken in slow cooker. In a bowl, combine barbecue sauce, dressing, brown sugar and Worcestershire sauce. Pour over chicken. Cover and cook on low for 5 hours.
2. Remove chicken to a cutting board and shred with 2 forks. In a small bowl, mix cornstarch and chicken broth. Stir into sauce in slow cooker, cover and cook until sauce is thickened and heated through, 5 to 10 minutes. Return chicken to cooker, stir, cover and continue cooking on low for 45 minutes. Serve chicken on whole-grain buns, over brown rice or with baked potatoes if you like.