Ingredients 150g grapes 1 lemon olive oil salt black pepper 60 g shelled walnuts 1 tsp English mustard 250 ml fat-free natural yoghurt 6 sprigs of fresh tarragon 2 sticks of celery 2 crisp eating apples 1 Romaine lettuce Method Preheat the oven to 180ºC/350ºF/gas 4. Place the grapes on a baking tray, finely grate over the zest from ½ ...