Cast Iron
A heavy, thick-walled cooking vessel made from iron alloy — the preferred pan for steak searing due to its exceptional thermal mass.
Cast iron cookware is made from an iron-carbon alloy cast in a mold, producing heavy, thick-walled pans with exceptional heat retention. A standard 12-inch Lodge skillet weighs about 8 pounds — most of that weight is thermal mass that stores enormous amounts of heat energy.
Why cast iron is ideal for searing: The critical advantage is thermal mass, not thermal conductivity. Cast iron's conductivity (52 W/m·K) is actually lower than aluminum (205) or copper (385). But its mass means it stores far more total energy at a given temperature. When a cold steak contacts a preheated cast iron pan, the pan drops roughly 80°F — from 650°F to 570°F. A thin stainless pan drops 250°F to 400°F. That 170°F difference means dramatically faster Maillard browning on the cast iron.
Preheating protocol: Cast iron's mass also means it takes longer to heat up. Preheat for at least 5 minutes on maximum stovetop heat. The center of the pan heats last (cast iron's poor conductivity means uneven heating). For the most even preheat, start in a 500°F oven for 20 minutes, then transfer to the stovetop.
Seasoning: Cast iron develops a polymerized oil coating ("seasoning") that provides a non-stick surface and prevents rust. High-heat searing builds seasoning naturally. Avoid soap-scrubbing after use — hot water and a scraper preserve the seasoning.
Cost: A Lodge 12-inch cast iron skillet costs about $30 and will last literally forever with basic care. It's the highest-value cooking tool available for steak.