01 - Combine smoked paprika, brown sugar, kosher salt, black pepper, garlic powder, onion powder, and cayenne pepper in a small bowl.
02 - Rub the spice blend evenly over the entire beef chuck roast.
03 - Set the seasoned beef into the slow cooker base.
04 - Pour beef broth, barbecue sauce, Worcestershire sauce, and apple cider vinegar over the beef.
05 - Cover and cook on low heat for 8 hours until the meat is tender and shreds easily.
06 - Remove beef from slow cooker, shred with two forks, removing excess fat.
07 - Return shredded beef to the slow cooker and mix thoroughly with cooking liquids.
08 - Toast sandwich buns if desired to enhance texture.
09 - Pile pulled beef onto buns, top with coleslaw and extra barbecue sauce if preferred.
10 - Serve sandwiches immediately while warm.