Allow your roast to come to room temperature. (Remove it from the refrigerator at least an hour before you are planning to cook it.)

Season the roast with salt and pepper. rub this all over the meat)

Heat the oil over medium high heat in a skillet. Add the roast to the skillet and sear it on all sides. (Leave it on one side for about 5 minutes until it is browned, then turn to another side, and continue until all the meat is browned.)

Place the beef and sliced onions into the slow cooker. Mix together the beef broth, garlic, beef bouillon powder, soy sauce, worcestershire sauce, rosemary and thyme in a bowl then add to the slow cooker as well.

Cook the roast for 8 hours on low or 4 hours on high.

Remove the roast from the slow cooker, place it on a cutting board, and cover it with tin foil. (The roast should rest for at least 30 minutes before slicing.)

While the roast is resting, skim any noticeable fat from the juice left in the slow cooker.

Slice the beef thinly, across the grain. (It may be so tender that it pulls apart easily, this works perfectly, too!)

Prepare the sandwiches by slicing open the rolls, piling on the thinly sliced beef, the onions (I remove these from the slow cooker as needed with tongs), and cheese (I like to use 2 slices per sandwich). If you would like to toast the sandwich and melt the cheese, place the open sandwiches on a baking tray into a 350 degree F oven and bake for about 5 minutes or until the cheese is melted.

Serve the au jus on the side for dipping.