Prepare the Ribs: Trim the spare ribs into a uniform St. Louis rectangle by removing the brisket flap and rib tips.
Apply the Binder: Pat the meat dry with paper towels and apply a thin layer of yellow mustard to all sides of the racks.
Season: Apply a heavy coating to the ribs, starting with the bone side.
Setup the Grill: Prepare your Big Green Egg for indirect cooking with the ConvEGGtor (legs up) and preheat to 200°F.
Add Smoke Wood: Place 3 to 4 large chunks of Hickory wood into the hot coals and wait for the smoke to run thin and blue.
The First Smoke: Place the ribs into a rib rack on the grate and smoke at 200°F for 3 hours to set the bark.
The Wrap: Remove the ribs from the grill and wrap each rack tightly in heavy duty aluminum foil.
The Braise: Place the foiled ribs back on the grill and continue cooking at 200°F for 1 hour to tenderize.
Bumping the Heat: Remove the ribs from the foil, discard the liquid, and increase the Big Green Egg temperature to 250°F.
The Glaze: Place the ribs back on the grate meat-side up and brush a generous layer of BBQ sauce over the top.
The Set: Cook for an additional 45 to 60 minutes until the sauce is tacky and the ribs pass the bend test.
Check for Doneness: Ensure the meat has pulled back from the bones and the internal temperature is between 203°F and 205°F.
The Rest: Remove the ribs from the grill and let them rest on a cutting board for 15 minutes before slicing.
Serve: Slice the ribs between the bones and serve immediately while warm.