Rub the ribs with the yellow mustard. Stir together the salt, pepper, and cayenne, then evenly season the ribs on both sides. Let meat come to room temperature, which will take about an hour. (If you want the rub to sit on the meat longer, put it in the refrigerator and then bring to room temperature before you cook it).
Place a quarter cup of wood chips in the bottom of your stovetop smoker (I like to use oak), place slabs of ribs on the rack, and then place on the stove over high heat with the lid ajar. When wafts of smoke leave the smoker, close the lid and turn heat down to medium low. Cook meat in the smoker for 2 hours.
Preheat the oven to 225° F. After 2 hours, take the meat out of the smoker. Place it in a pan and pour over it a half cup of apple juice. Tightly cover it with foil and cook in the oven an hour.
After an hour, take the meat out the liquid and run it under the broiler for a few minutes on each side. Ribs should be tender with a bit of a pull and a nice crust.
Notes
Note: If you don’t have a stovetop smoker, I reckon you could brown the ribs in a skillet, and then braise them in the oven for three hours before running them under the broiler. If you want to make babyback ribs, they take less time to cook, about an hour less. Beef ribs should take about an hour more.