Tuna niçoise salad with garlic and herb dressing

Method

1. Make the dressing by whisking the vinegar with the sugar, garlic and herbs and season. Gradually whisk in the oil until you have a thick dressing.
2. Heat a griddle pan until smoking. Brush the tuna with olive oil, season and griddle for 1-2 minutes each side until seared but still raw in the centre. Set aside. Blanch the beans in a pan of boiling water for 2 minutes then drain and refresh in cold water. In a large bowl, mix the green beans, tomatoes, black olives and lettuce.
3. Toss the salad with the dressing, slice the tuna thickly and place on top.