Prepare Cool Smoke BBQ Rub by mixing all of the ingredients in a medium sized mixing bowl. Transfer rub into a shaker.
Using the shaker, dust both sides of the rib racks generously, and let them sit at room temperature, uncovered, for 1 hour before cooking.
When you are ready to cook, heat the smoker to 275 degrees F pit temperature. Alternatively, heat a grill to 275 degrees F, using a 2-Zone setup, with 3 to 4 chunks of your favorite wood, in addition to the charcoal or gas.
Place the ribs meat-side-up in the smoker, or on the grill over the indirect heat, and cook 2 hours, spraying the spareribs with apple juice every 30 minutes to moisten.
Prepare the Cool Smoke Barbecue Sauce in a saucepan. Transfer the pan to a burner and put it on low heat just to simmer and let those flavors meld.
In a small bowl, stir 1 cup Cool Smoke Barbecue Sauce together with ¼ cup honey and 2 teaspoons apple cider vinegar and set aside.
Cut 2 (18 x 24-inch) lengths of foil to wrap each rib rack in a tight package.
When the ribs have cooked 2 hours, transfer them from the grill and place each rack meat-side-down on the foil. Drizzle the ribs evenly on both sides with the butter, ¼ cup honey, and the light brown sugar (optional).
Wrap each rack tightly in the foil, being careful not to puncture.
Return the rib packages meat-side-down to the smoker, or to the cool side of a grill, close the lid, and cook another 2 to 2 ½ hours, or until the meat is tender.
The ribs are done when a meat thermometer placed in the thickest part of the meat reads an internal temperature of 203 to 205 degrees F. Open the foil package and use a skewer, or a toothpick, to check for tenderness.
Remove from the heat, carefully unwrap the ribs, and discard the foil.
Brush Cool Smoke Barbecue Sauce on both sides of the ribs to coat and return them meat-side-up to the smoker or grill over indirect heat. Cook 15 minutes to set the sauce. Watch them carefully so you do not burn or overset the sauce.
Serve immediately, with any remaining sauce on the side.