Prep the Ribs: Remove the ribs from the package and pat them completely dry with paper towels. On the bone side, slide a knife under the thin, shiny membrane (the silver skin), lift it, grab it with a paper towel, and pull it off completely.
Apply the Binder & Rub: Lightly coat the ribs on all sides with the yellow mustard. In a bowl, mix all the rub ingredients together. Generously sprinkle the rub over the ribs, pressing it into the meat to create a uniform, even coating on all sides.
Preheat the Smoker: Preheat your smoker to 225°F (107°C). Add your wood chunks to the fire.
Smoke: Place the ribs directly on the grill grates, bone-side down. Close the lid and smoke for 3 hours. Do not open the lid often.
Wrap (Optional): After 3 hours, place the ribs meat-side down on a large sheet of heavy-duty aluminum foil. You can add a few tablespoons of apple juice or butter on top if desired. Wrap the ribs tightly to create a sealed packet. Return to the smoker for 2 more hours.
Set the Bark: Carefully unwrap the ribs and place them back on the smoker grates, meat-side up. Cook for another 1-2 hours, or until the bark is dark and crispy and the ribs are tender.
Rest: Remove the ribs from the smoker, tent loosely with foil, and let them rest for at least 30 minutes before slicing and serving.