Combine the celery salt, garlic powder and onion powder; rub over brisket. Place in a 5-qt. slow cooker. Combine liquid smoke if desired and hot pepper sauce; pour over brisket. Cover and cook on low for 6-8 hours or until meat is tender.
Remove beef and cool slightly. Discard all but 1/2 cup cooking juices; whisk barbecue sauce into cooking juices. Shred meat with two forks; return to slow cooker and mix well. Heat through. Serve about 1/3 cup meat mixture on each roll.