** For a very tender brisket, sous vide first! Place brisket with plastic wrap still in tact and sealed inside sous vide water. Set temperature to 135° for 48 hours. Then remove and prepare as directed below.
Prepare the night before: In a small bowl, mix together dry seasonings, beef broth, and mustard. Place brisket in aluminum pan. Spread mixture all over brisket, top and bottom. Place brisket in pan, fat side up. Cover with aluminum foil. Place in refrigerator overnight.
Take brisket out of refrigerator 1 hour before cooking to reach room temperature. Fill smoker container with hardwood BBQ pellets. Mesquite is a good flavor for this recipe. Prepare smoker by placing 2-3 long sheets of aluminum foil along the bottom of the smoker element, underneath the rack, for easy cleanup. Brush grill rack clean.
Set smoker to smoke. Once it starts smoking, set temperature to 225 degrees F. Smoke brisket in the aluminum pan – inserting meat probes if you're using one.
At the start of the 2nd hour, baste with juices that accumulate in the pan every hour. After 4 hours, check the temperature of the meat with probes or thermometer. Should be 160°.
Cover pan with aluminum foil once it reaches this temperature and smoke until meat reaches 195° F, total time will take 12-18 hours depending on thickness and size.
Remove from smoker and allow brisket to sit at room temperature for 1 hour. Cut across grain and serve with pan drippings or your favorite BBQ sauce.