Grillade of Tuna with Olive Oil Mash

3. Put all the ingredients for the dressing into a bowl, season with black pepper and whisk together. Stir into the tomato sauce and keep warm.

3. For the olive oil mash, cook the potatoes in boiling salted water until tender, then drain. Add the cream, olive oil, chicken stock, garlic and salt and mash until smooth. Set aside and keep warm.

4. For the fish and marinade, place a lightly oiled cast-iron ridged pan over a high heat. Mix the olive oil with the thyme leaves. Brush the tuna with the thyme oil and season well with sea salt and black pepper. When the pan is very hot, put 2 of the tuna steaks on it and cook for 4-5 minutes on each side, pressing down firmly with the back of a fish slice to help mark the fish with lines from the griddle. Put to one side and repeat with the remaining 2 tuna steaks.

5. To serve, put the tuna on 4 warmed plates and spoon the olive oil mash to one side. Using a teaspoon, spoon little pools of the sauce to the other side of the fish.