
Cook on low for 8 to 10 hours. The more racks in the pot, the longer you'll need to cook.
Optional step: Gently remove the racks and lay them out on a foil lined baking tray. Add more barbecue sauce on top. Broil under a broiler for 3-5 minutes until the barbecue sauce starts to bubble and caramelize.
(from www.thestayathomechef.com)