Season the beef roast with salt and pepper.
Heat a large skillet over medium-high heat and brown the beef on all sides.
Transfer the beef to a slow cooker.
Add sliced onion, garlic, Worcestershire sauce, thyme, and beef broth to the slow cooker.
Cover and cook on low for 4 hours or until the beef is tender.
Remove the beef and shred it using two forks.
Strain the broth and set aside the liquid.
Preheat the oven to 350°F (175°C).
Place shredded beef back in the broth to soak up the flavors.
Fill hoagie rolls with the beef mixture and cheese.
Bake for about 10 minutes, until the cheese melts.
Serve with a small bowl of the strained broth for dipping.