01 - In a small bowl, combine smoked paprika, garlic powder, onion powder, kosher salt, black pepper, and chili powder. Mix until evenly blended, then rub the seasoning mixture thoroughly over all surfaces of the trimmed chuck roast.
02 - Transfer the seasoned chuck roast into the slow cooker, positioning it flat and centered for even cooking.
03 - In a mixing bowl, whisk together the barbecue sauce, beef broth, apple cider vinegar, brown sugar, and Worcestershire sauce until the sugar dissolves and the mixture is smooth. Pour the sauce evenly over the beef in the slow cooker.
04 - Cover the slow cooker and cook on the low setting for 8 hours, or until the beef is fork-tender and pulls apart with minimal effort.
05 - Carefully remove the beef from the slow cooker and place it on a cutting board. Using two forks, shred the meat along the grain, discarding any large pieces of fat. Return the shredded beef to the slow cooker and stir to coat every strand in the sauce.
06 - Pile the saucy pulled beef onto burger buns or sandwich rolls and top with coleslaw, or serve over rice as desired.