Cooking Steps

1. Preheat a grill or smoker to 250 degrees.
   
2. In a small bowl, combine the salt, sugar, paprika, pepper, garlic powder and onion powder. Coat the entire brisket with the spice mixture. Place the brisket in the smoker or over indirect heat, if using a grill. Take care to keep the smoker or grill at a consistent temperature. Cook the brisket until the internal temperature has reached 200 degrees, about five hours.
   
3. Carefully transfer the brisket onto two layers of heavy duty aluminum foil. Tightly wrap the meat and let rest to slowly bring down the internal temperature and keep the meat very tender, about two hours. Remove the foil and discard.
   
4. Slicing against the grain, cut into thin slices and reserve any juices that may accumulate.
   
5. To build a sandwich, preheat the broiler to the highest setting. Butter both sides of two slices of bread and arrange on a baking sheet. Broil both sides of the bread until toasted as desired, about three minutes per side.
   
6. Reserve one slice of toast at room temperature and spread with a thin layer of Dijon mustard.
   
7. Top the other piece of toast with four ounces of smoked brisket, a layer of sauerkraut, and two slices of cheese. Broil until the cheese is melted and bubbling, about five minutes.
   
8. Top with the reserved Dijon toast. Cut in half lengthwise and serve warm.