Begin by preparing the dry rub. In a small bowl, combine the brown sugar, paprika, garlic powder, onion powder, salt, black pepper, and cayenne pepper. Mix well to ensure even distribution of the spices.
Pat the Boston Butt dry with paper towels. Massage the dry rub into the meat, covering all sides generously. For optimal flavor, wrap the seasoned meat in plastic wrap and refrigerate overnight.
Preheat your grill or smoker to a low and steady temperature of 225°F (107°C). If using a smoker, add wood chips or chunks to infuse the meat with a smoky flavor.
Place the Boston Butt on the grill or smoker, fat side up, and close the lid. Allow it to cook slowly for the estimated cook time, maintaining a consistent temperature.
After the initial 4 hours, you can start basting the meat with your preferred barbecue sauce if desired. Baste every hour to enhance the flavor and create a caramelized glaze.
Using a meat thermometer, check the internal temperature of the Boston Butt. Once it reaches 145°F (63°C), it is safe to remove from the grill or smoker.
Carefully transfer the cooked Boston Butt to a cutting board and tent it with foil. Allow it to rest for 15-20 minutes to allow the juices to redistribute.
Using forks or your hands, shred the meat into small pieces, discarding any excess fat or bone.
Serve the succulent pulled pork on buns or alongside your favorite sides. Feel free to drizzle additional barbecue sauce for extra flavor.