Spray the bottom of a 6 quart slow cooker with non-stick spray and lay the chicken breasts in. 2 pounds boneless skinless chicken breasts In a small bowl, mix up the cayenne pepper, paprika and garlic salt. Sprinkle the seasoning all over the chicken. Sprinkle on the brown sugar. Drizzle the honey all over the top of the chicken. Pour in the vinegar. Place the butter on top. Cover and cook on LOW for 4 hours or HIGH for 2 hours. Once cooked, use two forks to shred the chicken right in the slow cooker. Serve on soft buns with pickle slices.