In a small bowl, stir together the brown sugar, applewood BBQ seasoning, and chipotle powder.
In another bowl, whisk together the chicken broth, apple cider vinegar, 1/2 cup BBQ sauce, and hickory smoke.
Pour the broth mixture into the bottom of your slow cooker.
Trim any silver skin from the pork.
Rub the pork all over with yellow mustard.
Pat the seasoning mixture onto all sides of the pork, pressing gently so it sticks.
Place the pork into the slow cooker. Sprinkle any remaining seasoning over the top and scatter the butter pieces across the pork.
Cook on LOW for 8 hours.
At the 7.5‑hour mark, shred the pork with two forks and stir in the remaining 1 cup BBQ sauce.
Let it cook for the final 30 minutes, then serve on your favorite rolls.