Boil the potatoes with their skin on. Then peel, cut into bite-sized pieces and place in a bowl. Cut the gherkins into fine slices. Peel the onion and chop finely. Add both to the potatoes in the bowl. Carefully stir in 1 tablespoon mayonnaise.
Mix a marinade from the water with olive oil, balsamic vinegar, salt and pepper (if it is too acidic, you can add 1 teaspoon of sugar). Pour this marinade over the potatoes. Now sprinkle with dill, parsley and chives and stir well. Let it steep for approx. 20 minutes until eaten.