Preheat Oven to 275°F (135°C)

Prepare the Pulled Pork:

• In a bowl, combine brown sugar, onion powder, garlic powder, smoked paprika, black pepper, salt, cayenne pepper, oregano or thyme, and cumin.
• At medium heart, add the Garlic olive oil in your Dutch Oven and when hot add the sliced onions and sauté them until light golden brown.  
• Trim excess fat from the pork shoulder if necessary.
• Rub the spice mixture evenly all over the pork shoulder, giving it a good massage.
• Place the pork shoulder on top of the onions, fat side up.
• Cover the Dutch oven with a lid or aluminum foil, sealing it tightly.
• Place the Dutch oven in the preheated oven and roast for approximately 5-6 hours, or until the pork is tender and can easily be pulled apart with a fork. Baste with some of the rendered juices every hour if you can.
• After 5-6 hours, increase the oven temperature to 400°F (205°C) and remove the lid or foil. 
• Continue roasting for an additional 30-60 minutes until the pork develops a beautiful crust.
• Once done, remove the pork from the oven, and let it rest for about 30 minutes. During this time, you can prepare the barbecue sauce and coleslaw.

Prepare the Barbecue Sauce:

• In a mixing bowl, combine ketchup, honey, white vinegar, molasses, corn syrup, Dijon mustard, Worcestershire sauce, cayenne pepper, onion powder, garlic powder, salt, and black pepper.
• Add hot sauce, liquid smoke and mix well.  
• Optionally, add Bourbon to the sauce for extra flavor. Start with 1-2 tablespoons, adjusting to taste.  Taste the sauce and adjust the seasonings or heat level according to your preference.  Set the barbecue sauce aside for serving.

Assembling the Pulled Pork Sandwich:

• While the pork is resting, gently reheat the reserved cooked onions if desired.
• Pull the tender pork apart using two forks to create shreds.
• Place a generous portion of pulled pork on the bottom half of each Brioche Bun.
• Drizzle a spoonful of barbecue sauce over the pork.
• Optionally, add a layer of coleslaw for added texture and freshness.
• If you like, top the sandwich with some of the reserved cooked Onions.
• Place the top half of the Brioche Bun on the sandwich to complete it.
• Serve your Perfect Pulled Pork Sandwiches immediately, accompanied by extra barbecue sauce for dipping and your favorite sides.
• Enjoy this flavorful, mouthwatering pulled pork sandwich that's been slow-cooked to perfection and generously sauced to satisfy your barbecue cravings!