Preheat oven to 400 degrees. Season ribs all over with salt and pepper. Stack slabs on a large piece of heavy-duty foil; seal tightly, and place on a rimmed baking sheet. Cook until meat is fork-tender, about 1 1/2 hours.
Heat grill to medium-high; lightly oil grates. Remove ribs from foil (discard foil); brush with sauce, coating rounded side well. Grill until nicely browned, 3 to 4 minutes. Serve with more sauce.