Combine basil, coconut milk, Sriracha, garlic thai chili paste, soy sauce, onion and cilantro in the slow cooker. Stir.Using a double layer of paper towels pull the skin off of the chicken legs. Add the now skinless chicken legs into the slow cooker. Nestle them into the sauce.Cover the slow cooker and cook on LOW for 6-8 hours, Chicken will be very tender.Serve the chicken and sauce over rice and top with extra cilantro.