01 - Preheat oven to 300°F. Pat the beef chuck roast completely dry with paper towels. In a small bowl, combine kosher salt, black pepper, smoked paprika, garlic powder, and onion powder. Rub the spice mixture evenly over all surfaces of the beef.
02 - Heat olive oil in a large Dutch oven over medium-high heat until shimmering. Sear the seasoned beef on all sides until deeply browned, approximately 2-3 minutes per side. This creates a flavorful crust.
03 - Pour beef broth, apple cider vinegar, and Worcestershire sauce into the Dutch oven around the beef. Cover tightly with the heavy lid or aluminum foil. Transfer to the preheated oven and roast for 4 to 4.5 hours until the beef is fork-tender and shreds effortlessly.
04 - While the beef roasts, combine ketchup, apple cider vinegar, brown sugar, molasses, Worcestershire sauce, smoked paprika, garlic powder, onion powder, black pepper, and cayenne pepper in a saucepan. Simmer over low heat for 10-15 minutes, stirring occasionally. Adjust seasoning to taste.
05 - Remove the cooked beef from the oven and transfer to a large bowl. Using two forks, shred the meat completely. Skim excess fat from the cooking liquid, then add approximately 1/2 cup of the liquid back into the shredded beef for moisture. Mix in about half the BBQ sauce, reserving the remainder for serving.
06 - Pile the sauced pulled beef generously onto the bottom halves of the buns. Drizzle with additional BBQ sauce if desired. Top with red onion slices, lettuce leaves, and pickle chips. Place the bun tops and serve immediately.