01 - Arrange sliced onions and minced garlic evenly across the bottom of the slow cooker insert.
02 - Rub the chuck roast thoroughly with salt, pepper, thyme, and rosemary, pressing the spices into the meat. Place the seasoned roast directly on top of the onion layer.
03 - Pour the beef broth, soy sauce, and Worcestershire sauce over the beef and onions, ensuring the meat is partially submerged.
04 - Cover and cook on low heat for 8 hours until the beef is fork-tender and easily pulls apart.
05 - Transfer the cooked beef to a cutting board or large plate. Using two forks, shred the meat into bite-sized pieces. Return the shredded beef to the slow cooker and stir well to coat with the accumulated juices.
06 - Preheat your oven's broiler. Split the hoagie rolls horizontally and fill each with an equal portion of shredded beef. Top with a slice of provolone or Swiss cheese if desired.
07 - Arrange the assembled sandwiches on a baking sheet. Place under the broiler for 2 to 3 minutes, watching closely, until the cheese is melted and bubbly and the rolls are lightly toasted.
08 - Transfer the sandwiches to plates. Ladle the remaining cooking liquid from the slow cooker into small bowls and serve alongside for dipping.