Method
Cut any particularly big potatoes in half and put them into a large saucepan, then cover them with cold water. Put the pan on a medium-high heat and bring it up to the boil, then simmer for 8-10 minutes, or until the potatoes are tender when pierced with the tip of a sharp knife. Drain the potatoes and put them back into the dry pan (off the heat) to keep warm. To make the dressing, put the oil, vinegar and mustard into a jug or bowl and whisk them together, then season to your taste with salt and freshly ground black pepper. Pour the dressing into the dry pan with the cooked potatoes, then add the prepared herbs and use your hands to turn everything gently two or three times, until well mixed. Tumble everything out on to a serving platter and enjoy while the potatoes are still warm.