Trim excess fat off roast and sprinkle desired amount of salt/pepper on top.
In a bowl, combine the beef broth and Worcestershire sauce. *If you do not have Worcestershire sauce, steak sauce (such as A-1) can be substituted.
In a skillet (I use a cast iron), heat the olive oil over medium high heat. Sear the roast until all sides have a deep brown color.
Transfer roast to the slow cooker.
In the same skillet used previously, add the sliced onion and allow to cook for about 4-5 minutes.
Add the garlic to the onions and cook for 2-3 minutes.
Transfer the onion/garlic mixture to the slow cooker.
Pour the broth mixture into the slow cooker and place lid on top.
Cook on high for about 4 hours, or low for 6 hours. Beef should be very tender once cooked.
Carefully remove meat and shred or slice thinly.
Using a strainer, pour the juices from slow cooker to separate the onions from the broth mixture.
Place meat and onions back into the slow cooker to keep warm.
Pile meat and onions onto each roll and top with a cheese slice.
To melt cheese, if desired, place under a oven broiler for a few minutes.
Once cheese is melted, serve immediately with a side of au jus for dipping!!