Preheat oven to 225 degrees. Evenly sprinkle 1/2 Tbsp rib spice over each side of every slab. Place each rack of ribs, bone side down, into baking pan. Measure and carefully pour 1/4 cup cold tap water and 1/4 cup smoke flavoring, for each rack, into baking pan. DO NOT POUR MIXTURE OVER OR ONTO THE SEASONED RIBS. Cover baking pan tightly with Saran wrap (original Saran brand plastic wrap is oven safe to 250 degrees), making sure all corners and edges are tightly sealed. Then wrap over Saran wrap with aluminum foil, making sure to crimp and tightly seal edges. Place wrapped pan in oven using only top or bottom shelves if possible. Cook time is 2 to 2 1/2 hours. Set a timer.
After cooking, test ribs for doneness by pressing your finger on the meat between two bones (you should be able to press your finger all the way through the meat easily). If not tender, re-seal pan to cook. Test ribs at 15 minute intervals until proper tenderness is achieved. Cool at room temperature for 15 minutes BEFORE HANDLING.
One at a time, place racks of ribs on Saran wrap and evenly coat meat side of each rack with 2 ounces BBQ sauce. Wrap in Saran wrap. Allow to marinade refrigerated for 1 hour minimum.
After marinating, cook racks as needed. Place rack on grill meat side down and cook for 1 1/2 to 2 minutes. Using tongs, turn rack 1/4 turn and cook until juices begin to bubble from cut ends of bones. Flip rack, CAREFULLY by sliding tongs as far under rack as possible and cook, meat side up, for another 2 minutes. Ladle 2 ounces BBQ sauce evenly over top of rack and continue to heat for 2 minutes.
Special Instructions: The aluminum foil must completely cover the oven-safe Saran wrap and baking pan, and be crimped tightly around the sides. To ensure proper cooking and cooling, cook and store ribs in a single layer.Makes 4 Source: