First select a heavy covered pan, preferably what the French call a casserole à sauter, or sauteuse, big enough for the piece of tuna. Blanch the tuna in water to which has been added salt and lemon juice, take off its skin, and lard it with the fillets of anchovy.
Put the olive oil in the sauteuse and set it to warm. Slice thinly the onions and carrots and add them. Place the tuna on t