Rub the mustard all over the meat. Combine the brown sugar and seasonings and coat the entire brisket with it. Wrap in plastic and place in the refrigerator over night.
Take the meat out of the refrigerator and unwrap one hour before placing it into the smoker.
Turn the smoker to 225 degrees F, set the timer and close the vent.
Soak wood chips in water while the meat is coming to room temp.
Once the smoker has reached 225 degrees F. place the wood chips in the side slot and turn to dump them in the smoker box.
Place a pan of hot water on the lowest rack.
Place the brisket on a rack in the middle of the smoker, close the door and lock.
Open the vent one quarter of the way and turn the temperature down to 210 degrees F.
Allow the meat to smoke for 3-4 hours.
Preheat oven to 225 degrees F.
Take the meat out of the smoker and wrap tightly in foil and place on a baking sheet.
Cook in the oven for about two hours or until the internal temp reaches 190 degrees F.