To smoke pork loin, make sure the pork loin fits in the smoker. For a smaller smoker, the pork loin may need to be cut in half. Once the loin is cut to size and trimmed of any loose chunks or thin ends, you can season the pork.
Combine 1/4 cup paprika with 1/8 cup fresh ground black pepper, 2 tablespoons garlic powder, 2 tablespoons onion powder and 1 tablespoon of cayenne pepper, in addition to 1/4 cup coarse salt and 1/4 cup brown sugar. Rub the pork loin with the mixture and wrap it in plastic wrap. Refrigerate the meat overnight for best results.
Remove the pork loin from the plastic wrap and arrange it on a smoking wrap. Prepare wood chips for the smoker; apple wood chips are recommended. Smoke the meat until the internal temperature reaches 145 degrees Fahrenheit. For extra flavor, add apple juice to the smoker's liquid pan. The cooking time varies widely based on the size of the meat and temperature of the smoker, but smoking a pork loin generally takes about three hours.
Allow the pork loin to rest for at least 10 minutes after being removed from the smoker. Smoked pork tenderloin can be thinly sliced and served as is on toasted slices of baguette or used as sandwich meat. Alternatively, pork loin can be cubed or shredded and used for burritos or any recipe calling for carnitas.