Pat fillets thoroughly dry with paper towels — moisture kills your sear. Season both sides generously with kosher salt and black pepper; drizzle olive oil on the fish or add it to the pan. Let fillets rest at room temperature while the skillet heats. Check the flesh for pin bones and pull any out with tweezers. Keep a fish spatula close for pressing and flipping.

Heat a cast iron or stainless steel skillet over medium-high for 2–3 minutes until nearly smoking. Add high-heat oil and let it shimmer. Lay fillets skin-side down, pressing gently with a spatula for the first 30 seconds to prevent curling. Do not move them. Cook skin-side down 4–5 minutes until skin is crispy and flesh is opaque two-thirds up the side. Flip, reduce to medium, cook 1–2 minutes more. Total time: 8–12 minutes depending on thickness. For thick fillets, sear each side 2 minutes on the stovetop, then finish in a 177°C oven for 4–5 minutes.

Salmon is done when flesh flakes easily and turns fully opaque. Pull at 52°C internal (thickest part) — avoid going past 54°C or the flesh dries out. Rest on the plate 1–2 minutes. Finish with a squeeze of lemon and a pat of butter, or spoon over a sauce of your choice. Serve skin-side up to keep it crisp. Avoid: pan not hot enough (steaming, not searing), skipping the pat-dry (no browning), and flipping too early (it will release naturally when ready).