Screaming hot pan, 30 seconds per side.

Get a cast iron or stainless steel pan smoking hot. Pat the tuna dry, season with salt and pepper, and add a high-smoke-point oil like avocado or grapeseed. Sear for 30–45 seconds per side. That’s it. The inside stays rare because the outside cooks fast and the heat doesn’t have time to penetrate.

The common mistake is a pan that isn’t hot enough. If you use medium heat, the tuna cooks through before you get a crust. Also, don’t move the steak around—let it sit. And rest it for a minute off the heat after searing. The carryover will finish the center without turning it gray.

If your tuna is very thick (over an inch), you might need a quick second on each edge. But for standard steaks, two sides is plenty.

Your kitchen will smell great and the tuna will look like it’s from a restaurant.