Place the chicken breasts in the slow cooker.
In a medium bowl, whisk together the barbecue sauce, chicken broth, apple cider vinegar, brown sugar, smoked paprika, garlic powder, onion powder, salt, and black pepper until well combined.
Pour the sauce mixture evenly over the chicken breasts in the slow cooker.
Cover and cook on low for 6 hours, or until the chicken is tender and easily shredded with a fork.
Remove the chicken breasts from the slow cooker and place them on a large plate or cutting board.
Use two forks to shred the chicken into bite-sized pieces.
Return the shredded chicken to the slow cooker and stir it into the sauce to coat evenly.
Cook for an additional 10 minutes on low to allow the flavors to meld.
Serve the pulled chicken warm on sandwich buns, tacos, or over rice.