Preheat your smoker to 225°F/110°C
Peel the membrane from the back or under side of ribs. Start by using a knife in the corner of the rack. Once you get a grip of the corner of the membrane, slowly pull it off with your hands.
Apply the dijon mustard across all sides of the rack. Follow by applying the BBQ rub generously, pressing it to help it stick to the mustard.
Place ribs in the smoker and insert a meat thermometer into the flesh of the ribs.
Smoke the ribs for 3 hours. In this time the internal temperature of the meat should be around 175°F/80°C.
Remove the ribs from the smoker and wrap in aluminum foil. Re-insert the thermometer into the ribs and place the ribs back in the smoker.
Smoke for 1 further hour. In this time, the ribs should reach the target temperature of 195°F/90°C.
Remove the ribs from the smoker and unwrap. Brush the top surface of the ribs with BBQ sauce.
Place the ribs back in the smoker and allow to cook until the meat temperature reaches 195°F again.
Once we reach our target temperature, remove the ribs from the smoker and leave to cool for 10-15 minutes, before cutting up the ribs and serving.