Place the pork shoulder in the slow cooker. Add the BBQ sauce, garlic powder, smoked paprika, salt, and black pepper. Stir to coat the meat evenly.
Cover and cook on low for 8 hours until the pork shreds easily with two forks.
Shred the pork directly in the slow cooker and mix it with the sauce.
In a mixing bowl, combine the coleslaw mix, mayonnaise, and apple cider vinegar. Stir until the mix is coated.
Spoon the pulled pork onto the sandwich rolls and top each one with a scoop of slaw.