Prepare your smoker with a load of charcoal. Preheat to 250°F and place a water pan filled with boiling water over the coals. If you are using a gas grill, remove all of the grids, on one side, place a pan with hot water and replace the grids, on the other; place the Charcoal Tray directly on the burners. Light the burners below the charcoal tray and preheat the coals. Once they’re lit, turn the burners off and preheat the grill to 250°F.
Rub the meat with mustard and then coat it well with the seasoning of your choice. The thicker the seasoning, the better the bark(link if online by then).
Smoke the chuck roast for 4 to 6 hours. Use a Wireless Digital Thermometer
to watch the temperature. You are looking for 190°F, but it’s not ready until a fork will literally shred the beef on the smoker when you poke it.
As soon as the beef is on, make the coleslaw. Slaw is always best once it has been sitting for a while. In a large bowl, whisk together the mayo, horseradish mayo, cider vinegar, mustard, sugar, and olive oil. Add the kale, red cabbage, regular cabbage, and onion. Mix well, until everything is coated. Cover and place in the fridge until you’re ready to serve.
While you are waiting for the meat to smoke, you can also make the sauce. In a saucepan, combine the ketchup, butter, garlic, sugar, mustard powder, chili powder, and pinch of red chili flakes (or sambal). Bring it to a simmer for 10 to 15 minutes.
Once the beef is ready and you can literally shred it where it sits, remove it from the smoker. Allow the beef to rest for 15 minutes before shredding.
Pour the sauce over the shredded beef and use some sturdy tongs to mix it through. Butter and toast the buns, place your favorite deli style cheese on the bottom bun, add a heaping helping of saucy smoked beef and top that with some of the fresh slaw.
Pass out the napkins and dig in!