I use a basic Montreal style rub and add ground espresso powder to it. Under the pan I put in about 16 oz of beef broth with some sliced onions. Once the smoke is done, I pull the onions out and carmelize them in a pan. I defat the au jus and add some Johnies Au Jus to the broth and heat in a saucepan. I save this au jus for the second or third day for sandwiches. A good french roll, some provalone and the chuckie dipped into this au jus is amazing.
Good luck with the smoke