In a bowl, combine the brown sugar, paprika, smoked paprika, pepper, salt, garlic powder, onion powder, cayenne and mustard powder. Stir thoroughly until evenly mixed. This blend is the foundation of flavour and helps form the crust known as "bark" on the ribs.

Flip the ribs bone side up and slide a knife under the silvery membrane. Grip it with a paper towel and pull it off. Removing the membrane ensures better smoke penetration and tenderness.

Rub each rack lightly with yellow mustard to help the spices stick. Then coat all sides generously with the dry rub, pressing it into the meat. Let the ribs sit at room temperature for 30 minutes while you prepare the smoker.

Preheat your smoker to 120°C. Add a mix of fruit wood like apple or cherry for a sweet smoke. If using a gas grill, set it for indirect heat and use a smoker box or foil pouch filled with wood chips.

Place the ribs bone side down on the smoker grates. Close the lid and smoke for 3 hours. Maintain a steady temperature and avoid frequently opening the lid, which causes heat loss.

Mix together the mop sauce ingredients in a small bowl. After the first hour, lightly brush the ribs with the mop sauce every 45 minutes to keep them moist and build flavour layers.

After 3 hours of smoking, wrap each rack tightly in foil with a splash of mop sauce inside. Return to the smoker and cook for another 2 hours. This tenderises the meat and locks in moisture.

Unwrap the ribs and place them back on the smoker. Cook for 1 more hour to firm up the bark. During the final 30 minutes, brush with barbecue sauce if a glaze is desired.

Remove the ribs from the smoker and tent loosely with foil. Let them rest for 15 to 20 minutes to allow juices to redistribute. This ensures succulent, even bites.

Slice the ribs between the bones and serve with pickles, coleslaw or cornbread. Offer extra barbecue sauce on the side and garnish with a sprinkle of chopped parsley if desired.