Pan searing is a technique that works well for cooking fish steaks and thicker, shorter fillets of fish. If the fish has skin, score it on the skin side with a few vertical slashes. This will help the fillet from curling because the skin will shrink as it cooks. Dry the fish thoroughly and season with salt and pepper if desired.
Begin by heating a low-sided, well-seasoned skillet on the stovetop over medium-high heat until warm. Add about a teaspoon of oil, swirl the pan to evenly coat it, and heat until almost smoking. Add the seafood, placing the side you wish to present in to the hot pan first. Keep multiple pieces separated. Do not touch or move the seafood until it is browned on one side. You may have to adjust the heat to so that the seafood browns evenly but does not burn. Turn the seafood once it is about halfway cooked through-you can guess the halfway point by looking at the side of the fish, which will appear opaque on the side closest to the bottom of the pan and translucent on the side that is facing up. It may be useful to use two large, flat spatulas to help you flip the fish. Continue cooking on the second side until the fish begins to reach a final cooking temperature of 140 degrees, or the meat just begins to flake and becomes opaque. Remove from the pan, rest two minutes, and serve.