When frying in a small amount of oil, it’s best to heat the pan before adding the oil (this reduces oil breakdown into sticky polymers), or lightly oil the fish surfaces instead. If an especially crisp skin or crust is desired, the fish should be started on that side, pressed gently to maximize contact between hot pan and skin, and left long enough on high heat to develop the desired texture, then turned once and allowed to finish cooking through on lower heat. Thin fillets cook in just a few minutes per side, and require a hotter pan in order to brown quickly.