Start by patting the beef chuck roast dry with paper towels to remove moisture. Coat with yellow mustard.

In a bowl, mix together brown sugar, garlic powder, kosher salt, and black pepper. Rub this mixture thoroughly over the mustard-coated beef.

Preheat your smoker to 225°F. Place the roast on the grill grate and smoke for about 3 hours, or until the internal temperature reaches 160°F.

Wrap the roast in aluminum foil with a tablespoon of bourbon before returning it to smoke until it reaches 202°F, approximately 2 more hours.

Let it rest wrapped for at least 30 minutes to redistribute juices.

After resting, shred the beef using two forks into pieces and serve as desired.