1. Place chicken in slow cooker. Top with onions, then pineapple, then pour the whole bottle of bbq sauce over the whole thing.2. Cook on low setting for 8-10 hours. About an hour before it is done, carefully remove chicken from crockpot, shred it, and then return it to the cooker and stir so it can absorb some of the sauce as it finishes.3. Serve on hamburger rolls with extra bbq sauce on the side.