Remove membrane from the backside of the ribs by taking a sharp knife to lift the corner and then pull down and off using a paper towel for better grip. Cut the racks in thirds for easier handling and place in a shallow baking pan. Make the marinade and reserve ½ cup for later use. Pour the remaining marinade over the spareribs, make sure everything get coated, and then cover and marinate in refrigerator for at least 4 hours, but better if overnight. About an hour before cooking, remove from fridge and let sit at room temperature to take the chill off.
Set up grill for indirect cooking with medium-low heat (temperature around 300°F). Place drip pan under the grates where the ribs will sit and place grates back on the grill. For gas: make sure you have enough gas. For charcoal: bank the coals to one side. Every hour, check on the temperature and add 10 unlit briquettes or similar amount of charcoal.
Place the ribs bone-side down over drip pan. Set the humidifiers or water between the flame and the ribs, cover and cook 2 ½ to 3 hours or until the ribs are tender. Every 30 minutes or so, rotate ribs around the grill, if necessary to ensure even cooking.
About 15 to 20 minutes before ribs are done, flip or remove from rack so that they are meat side down. Brush liberally with the reserved soy marinade and close the grill cover and cook for 10 minutes. Flip ribs and brush with more marinade. Cook 5 to 10 minutes and transfer the ribs to a cutting board and cut into individual bones, if desired for serving. Serve hot or at room temperature.
Recipe by Grilling Outdoor Recipes powered by Bull Outdoor Products at http://www.grillingoutdoorrecipes.com/spicy-soy-ribs/