Instructions

Method
First, make the dressing. Tip the olives, anchovies and garlic into a large mortar and mash with a pestle until you have a very rough paste. Scrape into a bowl, if you like, stir in the lemon juice, olive oil and vinegar, then set aside.

Cook the potatoes in boiling water for 15 mins until tender, then drain and set aside. Cook the beans in boiling salted water for 4-5 mins until tender with a slight crunch. Drain, tip into iced water, then drain again and set aside. Boil a small pan.

Halve the potatoes and heat 2 tbsp oil in a non-stick frying pan. Place the potatoes cut-side down in the pan and sizzle for about 4 mins until golden and crisp. Toss the potatoes in the pan to brown on all sides, then turn up the heat and add the tomatoes. Fry the tomatoes for about 1 min until just starting to blister, then season. Splash in 1 tbsp of the balsamic vinegar, then turn off the heat and scatter over the basil.

To cook the tuna, place a non-stick frying pan over a high heat, then turn the heat down to medium and add 1 tbsp oil. Season the tuna generously, then sear for 4 mins, leaving it undisturbed in the pan to brown. Turn over and continue to cook for 4 mins on the other side. This will give you very rare tuna. For rare, cook for 2 mins more on each side and for well done, add another 4 mins on each side. Set the tuna aside to rest for a few mins.