Place the potatoes in a saucepan and cover with cold salted water. Bring to the boil and cook until the potatoes are tender. Drain the water, put the potatoes back in the pan and heat once more to remove any excess water. Remove from the heat.
Add the creme fraiche, dill and parsley and lightly crush with a fork, stirring at the same time. Season well with salt and pepper. Drizzle with the olive oil and finish with extra chopped dill before serving.