Put the potatoes in a large saucepan and bring to the boil. Cook the potatoes until tender (so that you can easily push a fork into them).
When the potatoes are cooked, drain them and return to the pan. Mash thoroughly until smooth.
Add the milk and Hellmann's mayonnaise and mix to combine.
As an extra special touch, sprinkle with chopped fresh herbs (such as chives) and serve.