Wash the chicken and pat it dry with paper towels. Line a baking sheet with two sheets of foil, place a wire cooling rack on top of the foil, and set the pan aside.
Whisk together the paprika, salt, black pepper, onion powder, chili powder, brown sugar, and celery salt in a small bowl.
Place the chicken in a large mixing bowl and pour the dry spice rub over the chicken. Use your hands to toss the chicken in the spices, making sure every piece of chicken is completely coated.
Use tongs to transfer the chicken to the baking sheet, arranging it in a single layer. Loosely tent the pan with foil and place it in the refrigerator overnight.
Preheat your oven to 400 degrees F. Take the chicken out of the refrigerator, remove the foil, and bake the chicken, uncovered, in the preheated oven for 25 minutes.
Meanwhile, add all of the BBQ sauce ingredients to a medium saucepan and heat the sauce over medium heat. Cover the pan and simmer the sauce for 25 minutes until reduced by half, stirring occasionally.
After 25 minutes, brush about ⅔ of the sauce over all of the chicken and continue to cook the chicken for an additional 20 minutes until it reaches an internal temperature of 165 degrees F. Keep the sauce warm while the chicken cooks.
Brush the remaining sauce over the chicken, turn on the oven broiler, and broil the chicken for 2 to 3 minutes until the exterior is caramelized. Allow the chicken to rest for 10 minutes then enjoy!