Warm Roast Beef Sandwiches

Changes I made: I improved the beef broth to be used as au jus by adding half a diced onion, 3 Bay leafs, a tsp thyme and fresh cracked black pepper to taste. I also ACTUALLY caramelized the onions with low heat for half an hour. I let the roast beef simmer during that time. The only reason this took any time at all was basically that particular decision.