That depends on the pan. Some ceramic pans are glazed, which helps keep food from sticking. Some stainless steel pans are also designed with a stick-resistant surface. And while uncommon, some au gratin pans have a nonstick interior like that found in other types of nonstick cookware. Regardless of the surface, your best strategy to limit sticking is to prep the interior of the pan by greasing it with butter or oil.