Combine these ingredients in a spice grinder to reduce to a fine powder. Work in batches if you have a smaller grinder. Combine well after grinding.
Cooking the Ribs
Remove the membrane from the back of the ribs. Use a dry paper towel to grip the edge and peel away in one piece.
Divide rack into 3-4 rib portions by cutting through the meat between the ribs. Rub ribs generously on all sides, setting aside 3-5 Tbsp of dry rub for finishing.
Place individual portions of rubbed ribs in vacuum bags and add 4 drops of liquid smoke to each bag. Fold the top of each bag while you add the ribs so you can keep the edges of the bags clean and the seal tight. Seal the bags and transfer to the refrigerator. Rest for 4 to 12 hours.
After resting the ribs in the fridge for the desired amount of time, set the precision cooker to 145°F for thick, extra meaty ribs or 165°F for thinner ribs (this is more common).
Add ribs to the water bath and cover with a lid or aluminum foil. Cook for 36 hours at 145° or 12 hours at 165.
Transfer cooked ribs to a large bowl of ice water after cooking.
Ribs can be stored in the fridge for up to 5 days after this step before finishing.
Finishing the Ribs
Remove ribs from vacuum bags and pat dry with paper towels.
Rub with remaining spice rub.
Prep the grill so that half the grill is lit or has coals burning and the other half is cooler. Close the lid and allow the grill to preheat to a medium temperature.
Oil the clean grates by rubbing them with an oil-dipped kitchen towel held by metal tongs.
Place the ribs with the thick meat side up on the cooler side of the grill. Cover and cook until the ribs are heated through and dry to the touch. Transfer the ribs to the hotter side of the grill and continue grilling, turning occasionally, until a crust has formed. Serve and enjoy!