Lightly grease the inside of your slow cooker with non-stick spray or a small amount of oil.

Place the chicken breasts or thighs in a single layer at the bottom of the pot.

In a medium mixing bowl, whisk together the BBQ sauce, apple cider vinegar, brown sugar, garlic powder, smoked paprika, and onion powder.

Season the chicken generously with salt and black pepper, then pour the sauce mixture evenly over the meat.

Cover the crockpot with its lid and set the temperature to LOW, cooking for 4 to 6 hours, or HIGH for 2 to 3 hours.

For best results, use the low setting, cooking until the chicken reaches 165°F and pulls apart easily.

Once the chicken is fully cooked, remove it and place it on a cutting board or plate.

Use two forks to shred the meat into bite-sized pieces.

Return the shredded chicken to the crockpot and toss thoroughly with the warm juices and sauce.

Let it sit on the 'warm' setting for another 10 to 15 minutes before serving it on your choice of buns or sides.