Combine water and apple cider in a large pot and bring to a rolling boil, then add remaining brine ingredients. If you don't have apple cider, apple juice will also work.Cover the brine and let boil for 10 minutes. Remove the brine from heat and allow it to cool to room temperature. Pour one cup of brine into a spray bottle.
Remove the membrane from the backside of the ribs. Think of this membrane as an impenetrable flavor barrier. Neither your rub nor your brine can get through this membrane, so removing it will make all the difference in the world to your finished ribs.
Submerge ribs into the room-temperature brine, making sure they are completely covered. I find it’s easiest to use a cheap disposable aluminum chafing pan for this, but use what you have.
Place ribs in the refrigerator for 24 hours.
While the ribs are brining, combine rub ingredients and put into a shaker bottle—set aside. You can make more of this if you like, I use this rub on other things as well; the cinnamon brings a unique flavor to various meats.
Light your grill and set up for two-zone cooking, establishing temperature at 285–300 °F.
Rub a very thin coat of vegetable oil onto the ribs. This will act as a binder for the rub.
Sprinkle the rub generously onto the racks of ribs. Ensure you cover the front, back, and sides of each rack.
Place the racks on a cutting board and gather your meat hooks. I like to use two hooks when I am hanging ribs. You can get away with one, but two just keeps things more secure.
Place the first meat hook onto the rack of ribs. I usually go about two bones deep on the first hook.Push the hook all the way through the meat, and ensure it lays flat against the ribs.
Note where the curvature of the first hook is when placing the second hook. I have cooked ribs with a single hook but I just feel better about the extra support. After inserting the second hook, connect it to the first hook for extra support and peace of mind.
Add apple wood chunks to hot coals and hang the ribs inside the barrel. Cook for about 3 hours, spritzing with the brine every 45 - 60 minutes. If you’re using a Kamado- style grill or kettle grill, just ensure you place the ribs over indirect heat.
Remove the ribs from cooker using a hook. Do not grab the hooks with bare hands! Allow to rest for about 10 minutes uncovered before slicing and serving.