Bake:
Preheat oven to 400°F. Place tuna steaks on a foil-or parchment-lined baking sheet. Bake for 8–10 minutes for medium-rare, or up to 12 minutes for medium-well, depending on thickness. Let rest for 2 minutes before slicing.
Grill:
Preheat grill to high heat. Oil grates well. Sear tuna for 2–3 minutes per side for a warm, pink center (medium-rare). For medium or beyond, grill an extra 1–2 minutes per side. Rest before serving to retain juices.
Skillet:
Heat a heavy-bottomed skillet or cast iron pan over high heat with a splash of neutral oil. Sear tuna steaks for 1.5–2 minutes per side for medium-rare. For a deeper crust, press down slightly during searing.
Air Fryer:
Preheat air fryer to 390°F. Lightly oil and season the tuna. Cook for 6–8 minutes, flipping halfway through. Best for achieving medium doneness. Adjust time for your preferred level of doneness.
Serving Suggestion:
Truffle mashed potatoes or sautéed spinach. Garnish with a drizzle of olive oil and a squeeze of lemon for brightness.