PREHEAT. Turn on smoker and preheat to 250F SEASON. Slather the roast with yellow mustard then season liberally with your favorite rub
SMOKE. Place the roast in your smoker and smoke until the internal temperature reaches 165F.
WRAP. Wrap the chuck roast in butcher paper or foil and smoke until the internal temperature reaches 195F
REST, CUT, AND SEASON. Allow the roast to rest for 20 minutes. Cut into 1.5" cubes and season with brown sugar, butter, and BBQ sauce and place them in a foil baking pan.
FINISH. Place the pan back in the smoker, and cook for more hour.