This method works best with boneless pieces of fish, either whole fillets or meaty portions of larger fish, skinless or not. This method works for many of the fish recipes on this site. And if you are looking specifically for salmon and trout recipes, click here.
2tablespoonsgrapeseed,safflower or peanut oil, or clarified butter
Lemon or limes for garnish
Take the fish out of the fridge and salt both sides well. Let them come to room temperature for 20 minutes.
Near the end of that time, heat a large steel or cast iron sauté pan over high heat. When it's hot, add the oil and swirl it around. Pat the fish dry with paper towels, and if it has skin, use a butter knife to scrape the skin dry; there is often slime on it still.
Have a metal spatula or a bacon press handy. Set the fish fillets, skin side (or the side where the skin used to be) down, and the instant they hit the pan, jiggle it so they don't stick. Set the bacon press down on the fillets to flatten them, or press down with the spatula. Keep the pressure on for 30 to 60 seconds.
Baste the exposed side of the fish with the hot oil by tipping the pan a little to collect the oil. Do this until the fish turns opaque, about 30 seconds to 1 minute, if the fish is thick.
Drop the heat to medium-high -- you want it to sound like bacon sizzling. Let the fish cook undisturbed until it wants to release from the pan, usually about 4 to 6 minutes. Jiggle the pan to see how it's going. With fish thinner than about 1 inch thick, you will not be flipping.
When the fish has mostly or completely released, use a metal spatula to flip thick fillets, which get cooked another 3 to 5 minutes, or to remove thinner fillets to serve. Set them skin side up and grind some pepper over them.
Keep in mind this method is far harder to pull off with fragile fillets that are either very soft or very thin. Some examples would be sardines, small flounder, small walleye or trout.