Spray a large (6 to 7 quart) slow cooker with cooking spray. Place the roast in slow cooker and add all remaining ingredients.
Cover with lid and cook on low heat for 4 hours. Remove roast to a cutting board. Remove any fat then slice roast thinly (about 1/4 inch a slice). Place meat back in slow cooker. Continue to cook on low heat for an additional 2 to 3 hours.
When ready to serve, remove roast slices from slow cooker. Strain au just into a large bowl to get rid of any large pieces of onion/seasoning.
Cut rolls in half and place on a large baking sheet. Spread each bottom half of buns with 1 Tablespoon cream cheese. Then top each with beef and one slice Provolone cheese.
Place in oven under broiler until cheese has melted. *Watch the entire time so they don't burn!* Serve sandwiches with au jus and enjoy!