Pan-Seared Tuna with Shallot Sauce

Pat the tuna steaks completely dry with kitchen paper. Season all surfaces generously with the flaky sea salt and black pepper. Set aside at room temperature while you prepare the shallots, garlic, and butter.

Place a heavy stainless-steel or cast-iron skillet over high heat for 2 minutes until it is smoking. Add the oil and swirl to coat.

Lay the tuna steaks in the pan — they should sear aggressively. Cook for 90 seconds without moving until a deep mahogany crust forms on the underside.

Flip the steaks and sear for a further 90 seconds on the second side. Use a meat thermometer to check the centre: the traditional French preparation is rare to medium-rare, pulled at 46–49°C — note this sits below the temperature considered safe for eliminating pathogens. Cook to 63°C if you prefer it fully cooked through. Transfer to a warm plate and tent loosely with foil.

Reduce the heat to medium. Add the sliced shallots to the same pan and cook for 8 minutes, stirring often, until they are completely softened and beginning to turn golden, scraping up the tuna fond from the base.

Add the garlic and thyme and cook for 1 minute until fragrant.

Pour in the white wine and let it bubble for 3 minutes until reduced by two-thirds.

Add the fish stock and sherry vinegar and simmer for 2 minutes until the sauce is lightly syrupy and coats the back of a spoon.

Remove the pan from the heat entirely. Add the cold butter cubes a few at a time, swirling the pan constantly to emulsify the butter into the sauce. Do not return to the heat or the sauce will break.

Taste and adjust seasoning. Spoon the shallot sauce over the rested tuna steaks, scatter with chopped parsley, and serve immediately with lemon wedges.