Method
- Take the salmon fillets out of the fridge 15 minutes before cooking so they cook more evenly; pat both sides completely dry with paper towels. Wet skin will not crisp and will make the fish stick to the pan.
- Season both sides of each fillet with 1/2 teaspoon of the salt and 1/4 teaspoon of the pepper total, pressing lightly so it sticks.
- Set a large heavy skillet (stainless steel or cast iron, 12 inches) over medium-high heat and add the olive oil. Heat for about 2 minutes until the oil shimmers and moves easily when you tilt the pan; a too-cool pan is the main reason skin sticks instead of crisping.
- Lay the fillets in the pan skin-side down, away from you to avoid splatter, and press each one gently with a spatula for 10 seconds so the skin makes full contact with the pan.
- Cook undisturbed for 5 to 6 minutes. Do not move or flip the fish during this time; you will see the flesh turn opaque pink about two-thirds of the way up the side, and the skin should look deep golden and release easily from the pan when you nudge it.
- Flip the fillets carefully with a thin fish spatula and cook the second side for 2 to 3 minutes more, until the salmon reaches an internal temperature of 125 to 130 F for medium (use an instant-read thermometer inserted into the thickest part) or 145 F if you prefer it fully cooked through. The flesh should flake easily with a fork when done.
- Transfer the salmon to a plate and tent loosely with foil to keep warm. Do not wash the pan; the browned bits left behind are flavor for the sauce.
- Reduce the heat to medium-low and add 1 tablespoon of the butter to the same pan. Add the minced garlic and cook for 30 seconds, stirring constantly, until fragrant but not browned; garlic burns quickly and turns bitter if left too long.
- Pour in the broth and lemon juice, scraping up the browned bits from the bottom of the pan with a wooden spoon. Simmer for 2 minutes until the liquid reduces slightly.
- Remove the pan from the heat and add the remaining 3 tablespoons of butter, swirling the pan constantly until the butter melts into a smooth, glossy sauce. Adding the butter off the heat and swirling rather than stirring keeps the sauce from separating into an oily puddle.
- Stir in the remaining 1/4 teaspoon salt and 1/4 teaspoon pepper.
- Spoon the lemon butter sauce over the salmon fillets, top with lemon slices and chopped parsley, and serve immediately.
Tips
If the skin sticks when you try to flip, it is not ready yet; give it another 30 to 60 seconds and it will release on its own.
Use a thin, flexible fish spatula rather than a rigid one to slide cleanly under the delicate fillet without tearing the skin.