- 2 x 140 g tuna steaks
- 2 1/2 tablespoons olive oil
- 100 g green beans, trimmed
- 1 tablespoon red wine vinegar
- 1 teaspoon dijon mustard
- a pinch of caster sugar
- 100 g baby cos lettuce leaves
- 12 red or yellow cherry tomatoes, halved
- 12 pitted kalamata olives
- Season the tuna on both sides with salt and freshly ground black pepper. Heat 2 teaspoons of the oil in a small non-stick frying pan over medium–high heat. Add the tuna and cook for 2–3 minutes on each side for medium–rare, or until cooked to your liking. Remove from the pan and leave to cool. Flake the flesh into chunks.
- Meanwhile, bring a small saucepan of water to a boil. Add the beans and cook for 2 minutes, or until just tender but still crisp. Drain and refresh under cold running water.
- Whisk together the remaining oil with the vinegar, mustard and sugar.
- Arrange the lettuce leaves on a plate or plates. Gently toss together the beans, tomatoes, olives, tuna and dressing in a bowl. Arrange over the lettuce and serve immediately.