Prepare the Rib Rub: In a small bowl, combine the brown sugar, paprika, garlic powder, onion powder, black pepper, and cayenne pepper (if using). Mix well.
Apply the Rub: Pat the pork ribs dry with paper towels. Generously coat both sides of the ribs with the prepared rub, pressing it in gently to adhere.
Preheat Your Smoker: Set your pellet smoker to 225°F (107°C). Use your favorite wood pellets, such as hickory or applewood, for a classic smoky flavor.
Smoke the Ribs: Place the seasoned ribs directly on the smoker grate, bone-side down. Smoke for 3 hours, or until the ribs have developed a deep reddish-brown color and a good bark.
Wrap the Ribs: Remove the ribs from the smoker. Lay out two large sheets of heavy-duty aluminum foil. Place the ribs on one sheet, then drizzle with apple cider vinegar. Seal the foil tightly around the ribs.
Continue Smoking: Return the wrapped ribs to the smoker and cook for another 1.5 to 2 hours, or until the meat is tender and pulls away easily from the bone.
Glaze and Finish: Carefully unwrap the ribs. Brush them generously with your favorite BBQ sauce. Return the ribs to the smoker, unwrapped, for another 15-20 minutes to allow the sauce to caramelize.
Rest and Serve: Remove the ribs from the smoker and let them rest for 10-15 minutes before slicing and serving. This allows the juices to redistribute, ensuring maximum moisture and flavor.