Add the sliced onion and the garlic to the bottom of the slow cooker.
Sprinkle the salt, pepper, thyme, and oregano on all sides of the roast and place the roast on top of the onions.
Sprinkle the onion soup mix, Worcestershire sauce, soy sauce, consommé, beef broth, and sherry over the roast.
Place the cover on the crock pot and cook on Low for 8-9 hours, or High for 4-5 hours, or until the meat is fall-apart tender. Remove the meat to a plate and shred. Set aside.
Strain out the onions and set aside. Reserve the drippings (jus), and use a fat separator if you want to remove some of the fat. Then pour the jus into individual serving bowl for dipping.
Butter and toast the buns if you want, then pile some of the shredded beef and reserved onion onto each roll and top with a couple slices of the provolone cheese (you can then broil them if you want to melt the cheese).
Serve each sandwich with a cup of the hot jus for dipping the sandwiches into.
Notes
*Can also use a boneless beef rib loin, tied, or a rump roast.