1 kg. tuna (a single piece),
2 or 3 garlic cloves,
some mint,
200 gr. tomato extract,
1 onion,
olive oil,
pepper,
2 bay leaves (or a piece of cinnamon).
Hole the tuna and place put garlic and mint in pieces. Tie the tuna and brown in oil.
Take the tuna out and in its juice brown grated onion and tomato extract (add some drops of water to dilute it). Now add 1 litre of water and put the tuna back in the pan, along with bay leaves (or cinnamon).
Dress with pepper (no salt because extract is usually salty) and cook on a low flame for about a hour. Serve with boiled potatoes.