In a bowl, whisk together ketchup, honey, apple cider vinegar, brown sugar, Worcestershire sauce, smoked paprika, garlic powder, onion powder, black pepper, cayenne pepper, and chicken broth.

Place the chicken thighs in the slow cooker and pour the sauce mixture over them, ensuring they are well coated.

Cover and cook on low for 7 hours (420 minutes).

After 7 hours, remove the chicken from the slow cooker and shred it with two forks; return the shredded chicken to the slow cooker and stir to coat with the remaining sauce.

Let the chicken sit on low for an additional 30 minutes to absorb more flavor.

While the chicken rests, combine shredded cabbage, shredded carrots, mayonnaise, apple cider vinegar, honey, Dijon mustard, salt, and pepper in a bowl; toss until evenly coated.

To assemble, place a generous portion of shredded BBQ chicken onto each bun, top with coleslaw, and serve immediately.

Use a food thermometer to verify the chicken reaches a safe temperature before serving.