Add the onion and garlic to the bottom of a slow cooker.
In a small mixing bowl combine the beef broth, soy sauce, Worcestershire sauce, and mustard. Pour into the crock pot.
Rub beef roast all over with salt and pepper. Place the roast on top of the onions in the crock pot. Add the bay leaves on each side of the roast.
Cover and cook on LOW for 7 hours.
Remove the roast and shred the meat using two forks. Return the beef to the broth, stir, and let it soak up the juices while you prepare the rolls.
Slice the rolls in half lengthwise. Toast on a baking sheet, cut side up, in a 350 degree F the oven until golden brown.
Remove the rolls from the oven. Divide the shredded beef evenly among the bottom halves of the rolls. Then cover each sandwich with two slices of provolone cheese. Return the bottom of the sandwiches to the oven until the cheese is melted.
Remove the french dip sandwiches from the oven. Place the top of each roll onto the sandwiches. Serve with a little bowl of the au jus from the slow cooker for dipping.
Notes
Nutritional information includes the sandwiches and all of the au jus left in the crock pot.