I would recommend giving the smoked mac and cheese recipe from ManCaveMeals a try. Here is the link to it.
I recently made a variation of it and it turned out great. Instead of Chorizo I used some pork tenderloin that I had left over and substituted some of my rib rub in place of the chipotle powder or my wife would have cried foul for it being too spicy, Also added a Panko bread crumb topping toward the end. I made it on my Performer with cherry wood smoke. Here are some pics of the way it turned out.
WSM, Performer, 22.5 & 18.5 OTG, SJG, mini WSM, Summit 420, Q100, C-G Akorn, and Schwenkgrill