Set Pellet Grill to 180°F. Let it preheat for 15 minutes.
Prep Ribs
Remove the membrane from the back of the ribs. In my experience, ribs bought from the store have their membrane still attached where as ribs purchased from a local butcher have theirs removed. It's not necessary to remove the membrane, but it is preferred as it doesn't break down while cooking and is hard to chew.To remove the membrane: Flip the rib so its bone side up. In the middle of the rack, work the tip of a butter knife in between the membrane and bone. Once you are able to separate the membrane from the bone enough to get your finger under it, use a paper towel to get a firm grip then tear the membrane off.
Use paper towel to remove excess moisture from the ribs.
Mix together the ketchup and vinegar. Brush on both sides of the ribs.
Mix your dry rub ingredients and then apply generously to both sides of the racks.
Smoke the Ribs
Place racks on the grill, meat side up. Close the lid and smoke for 3 hours. at 180°F. at the end of this, you will be at 130°F If you reach 130°F before 3 hours has elapsed, you can take the ribs off the grill and move to step 2.
Wrap the Ribs
Remove the ribs from the Smoker.
Increase smoker temperature to 225°F
Layout 4 pieces of aluminum foil. Each piece should be about 2 feet long. (a few inches longer than each rack of rib on either side of it.
for each rack: overlap the two pieces of foil so half of the foil is touching the other. Sprinkle the brown sugar, honey and red pepper flakes evenly over the foil where the rib rack will lay. Place Rib on top of this, meat side down, and seal the foil up. first lengthwise and on one end. Before sealing the final end, tip the ribs up and pour the shot of rum in (if using) then seal that end.The easiest way to seal foil is by folding it together. If you just scrunch it, you're likely to tear it or not completely seal it and then you will have a leak and then you will be sad.
Place the ribs on the now 225°F Grill. Meat side down. Insert a Temperature Probe into the wrapped ribs. just poke through the tinfoil and feel before inserting the probe that you are aiming for in between two bones.
Grill for 2 Hours. If you want Ribs to stay on the bone but be done you can cook them to an internal temperature of 180°F If you want them to fall off the bone you can cook them to an internal temperature of 195°F. If your ribs are reaching your desired internal temperature quicker than the 2 hours you can pull them off the grill and sauce them and put them back on and remove them at desired final temp. You can also choose not to add bbq sauce at the end. It's not entirely necessary as the wrap acts as a sauce.Perfect Bite: 180°FFall off the Bone: 195°F-205°F
Sauce
Unwrap the ribs and brush BBQ sauce on both sides. Discard the Foil.
Place the ribs directly on the grill and cook for 30 minutes - 1 hour more. Until the sauce has tacked up.