01 - Preheat oven to 300°F for the initial braising process.
02 - Rub beef chuck roast thoroughly with olive oil, then evenly coat with salt, black pepper, smoked paprika, garlic powder, and onion powder on all sides.
03 - Heat a large Dutch oven over medium-high heat. Sear seasoned beef on all sides until deeply browned, approximately 4-5 minutes per side. Remove beef and set aside on a plate.
04 - In the same Dutch oven, add sliced onions and minced garlic. Sauté for 2-3 minutes until onions are softened and fragrant, scraping up any browned bits from the bottom.
05 - Pour in beef broth, barbecue sauce, Worcestershire sauce, brown sugar, and apple cider vinegar. Stir well to combine and bring mixture to a gentle simmer.
06 - Return seared beef to the pot, nestling it into the liquid. Cover tightly with lid and transfer to the preheated oven.
07 - Braise for 4 hours, turning the beef once halfway through cooking, until meat is fork-tender and easily shreds apart.
08 - Remove beef from cooking liquid and shred using two forks. Skim excess fat from the braising liquid, then return shredded beef to pot and toss thoroughly to coat in juices.
09 - Increase oven temperature to 350°F. Slice slider buns in half horizontally and brush cut sides lightly with melted butter. Place on baking sheet and warm in oven for 5 minutes until lightly toasted.
10 - Pile warm pulled beef generously onto each bun bottom. Top with 1-2 dill pickle slices and cover with bun tops. Serve immediately while hot.