Cut pork butt into 1-2 inch slices then cube each slice.
Season pork cubes on each side with 3 tablespoons of bbq rub.
Smoke pork at 250°F for 2-3 hours or until they reach an internal temperature of 175°F. Spritz with apple juice every 30 minutes if pork looks dry and to help build bark.
Once the pork reaches 175°F place into an aluminum disposable pan with butter, brown sugar, bbq sauce and 1 tablespoon of bbq rub. Mix gently together and then cover with foil.
Place pan back into the smoker until the pork reaches 205°F. (About 1-2 hours)
Once pork is done, pull one corner of the foil back allowing it to vent for 15-20 minutes before serving.
