Place the beef chuck roast in your slow cooker. Season it generously with salt and pepper.

Lay the sliced onion and minced garlic over the roast.

In a bowl, whisk together the beef broth, Worcestershire sauce, and dried thyme. Pour this mixture over the roast and onions.

Cover the slow cooker and set it to low. Cook for about 8 hours, or until the meat is tender and shreds easily.

Transfer the roast to a cutting board and shred the meat using two forks, discarding large pieces of fat.

Stuff the shredded beef into hoagie rolls and top with sliced provolone cheese, if desired.

Broil briefly to melt the cheese.

Strain the cooking liquid into a bowl and skim off excess fat to serve as au jus for dipping.