Makes 3 full-rack servings or 6 half-rack servings
The term “St. Louis rib” has nothing to do with a cooking style or flavor profile—it refers to the way the meat is butchered: cut from the center of the spare ribs, which is the large, flat area from the flat belly side of a hog. Whereas baby back ribs have a pork chop flavor, the St. Louis cut tastes more like bacon, since it’s from the belly. As with baby backs, we prefer smaller ribs, which may be difficult to find, but most meat departments or specialty stores can help you out with special ordering. It’s (literally) worth noting that St. Louis ribs cost significantly less per pound than baby backs. If we hadn’t made our name cooking baby backs, we’d be all about St. Louis ribs at our restaurant.
Prep the meat: To remove the thin, papery membrane from the inner side of the ribs, lay each rack, bone side up, on a flat surface and slide the handle of a teaspoon between the membrane and the meat, working from one end all the way to the other. Use a paper towel to grab ahold of the membrane and pull firmly to peel the whole thing off. Then use the bowl end of the spoon to scrape away any extraneous fat on the bone side of the rack, between the bones. Don’t scrape all the way down to the bone, just remove any thick deposits. Turn the rack over and inspect the front. Use a sharp knife to trim off any scraggly edges and hard pieces of fat (which won’t render out during the cooking process).
Cut the racks in halves or thirds as needed to fit on the cooker. Lightly sprinkle each side with dry rub. You’ll be layering on rub several times during the cooking process, so don’t overdo it now. Set the ribs on a baking sheet, cover them with plastic wrap, and refrigerate until you’re ready to put them on the cooker.
Note: You can dust the ribs with dry rub up to 4 hours prior to cooking, but if they sit much longer than that, the salt in the rub will begin to pull moisture from the meat.
Set up the cooker for indirect cooking: Open the top and bottom vents. Pile 3 pounds of the charcoal in one half of the cooker, leaving the other half empty. Load a charcoal chimney one-quarter full of charcoal and light it. When the coals in the chimney are glowing, dump them on top of the pile of charcoal in the cooker. Set the wood on top of the coals, replace the grate, and put the ribs over the side with no coals (the indirect cooking area), bone side down. Close the lid.
Don’t open the cooker for 1 hour, but keep a close eye on the temperature (see page 84 for how best to assess and monitor cooker temperature); when it reaches 185°, which might happen very quickly, close the vents about halfway so that less air comes in to feed the fire and the heat in the cooker rises slowly. Let the temperature climb to between 225° and 250° (see page 77 for how to determine your target temperature). Maintain your target temperature for the duration of the cook.
Throughout the entirety of the cook, be on the lookout for fluctuations in cooker temperature; if it dips more than 5° below your target and opening the vents isn’t sufficient to bring it back up, you will need to add a few hot coals. If at any point the temperature climbs above your target by more than 5°, close the top and bottom vents even more so that even less air comes in to feed the fire.
After 1 hour, open the lid and check the edges of the ribs closest to the fire. If they look like they’re beginning to brown, rotate the racks, moving the pieces that are farthest away and placing them closest to the fire, and vice versa. (Do not flip the ribs over, now or at any other point during the cook.)
Close the lid and continue smoking the ribs for another 2 to 4 hours, monitoring the cooker temperature and checking every 20 minutes or so to see if the surface of the meat looks dry or moist. If the ribs look dry, mist them with some apple juice and sprinkle on another light coat of dry rub. Ribs “sweat” about three times during the smoking process, indicating that the seasoning from the dry rub and the flavor from the smoke are being absorbed into the meat. Never flip the ribs over; instead continue rotating them so each rack cooks evenly.
Prepare another round of charcoal in the chimney as needed. This cook should not require more charcoal than the initial amount, but we always keep some coals at the ready just in case more are needed to maintain the temperature.
After the ribs have been on the cooker for 3 hours, start checking for doneness every 20 minutes or so by lifting up one end of a rack. If the rack is still rigid like a board or bends only a little, the ribs need more time. When they’re done the rack will sway, bending in the middle.
Mop the ribs with a thin coat of sauce, then close the lid for just a minute to let it dry a bit. Mop with a second thin coat, give them a final sprinkle of dry rub, pull them off the cooker, and serve. Serve full or half racks, or cut into single or double bones to serve as an appetizer.