Combine the 7 rub ingredients in a bowl. Rub the mixture evenly over the chicken. Place the chicken on a heated grill pan or cast-iron pan coated with cooking spray. Cook for about 10 minutes or until no longer pink in the middle, flipping the chicken occasionally. Let the chicken stand for a few minutes and then shred it, using two forks.

To prepare the sauce, heat the canola or vegetable oil in a medium saucepan over medium heat. Add the onion and cook for about 5 minutes or until it is tender. Stir in the brown sugar, chili powder, garlic powder, and ground red pepper. Cook for 30 seconds. Then add the ketchup, cider vinegar, molasses, and mustard. Bring the sauce to a boil and then reduce the heat to a simmer for about 10 minutes, stirring occasionally. The sauce will be done when it has thickened, slightly. Lastly, stir in the shredded chicken and cook for about 2 more minutes (until the chicken is heated through).