Add the chicken, sauce, and butter (slice it up and lay on top of wings) to the slow cooker. Cook on HIGH for 2.5 hours. DO NOT open the lid while the wings are in the slow cooker, heat will escape and they will not cook.
After cooking time is done, take the wings out of the slow cooker, leaving the sauce in the slow cooker, and put the wings on a baking sheet.
Broil the wings in the oven for a few minutes on each side until browned and crisp.
Add the wings back to the slow cooker, and stir them back into the sauce.