Technical Stages :

• Soak the mushrooms for 15 minutes in warm water. Meanwhile, de-salt the anchovie fillets under cold running water.
• Chop together and very finely the mushrooms, anchovies and garlic cloves; put them in a large skillet with oil, flour, parlsey. Stir well and cook for 3-4 minutes over medium heat.
• Moisten with white wine and bring to a boiling point. If the sauce is too thick, dilute it with some water. Put the tuna slices, trying not to overlay them, season with salt and pepper if needed, cover and cook for 5 minutes.
• Turn the slices over, cover again and transfer the skillet in a preheated oven at 180°C or 356°F. Bake for 20 minutes, until tender.
• Using a small spatula, arrange the tuna on a service dish. Add the lemon juice and butter cut in chunks to the coking juice. Stir until the butter has melted, pour on the fish and serve.