Preheat oven to 350°F. Pat both sides of slabs dry with paper towels. Using a sharp knife, remove thin membrane from back of each slab by slicing into it and pulling it off with a paper towel. Divide Southern Barbecue Dry Rub evenly between slabs, rubbing on both sides of each. Press gently to adhere. Place slabs, meaty side up, on a wire rack on an aluminum foil-lined baking sheet, and let stand at room temperature 30 minutes.
Bake in preheated oven until meat begins to pull away from bones but is not yet tender, about 1 hour and 30 minutes. Increase oven temperature to 450°F. (Do not remove ribs from oven.)
Brush both sides of ribs with 1 cup Melting Pot Barbecue Sauce. Bake until ribs are very tender and caramelized, 35 to 45 minutes, brushing with another cup of sauce halfway through baking. Remove ribs from oven, and let stand at least 10 minutes. Serve ribs with remaining 2 cups sauce.