Gently cook potatoes in a large pan of simmering water for 20 minutes or until tender but still firm, drain and set aside

Blanche the beans in boiling water for 2 minutes, or until bright green and just tender. Drain the years as well and set aside

To make dressing: whisk all ingredients in a small bowl for 2 minutes until well combined. Serve salad hot or cold, pour over dressing no more than 5 minutes before serving otherwise salad will discolour