Place the potatoes in a saucepan. Add water to cover by 1 inch (2.5 cm) and 1 tablespoon salt, and bring to a boil over high heat. Lower the heat to medium and cook for 15 to 20 minutes, or until you can press against the potatoes with a spoon and feel them crush.
Just before the potatoes are ready, in a small saucepan, bring the milk to a boil and remove from the heat. Drain the potatoes and pass them through a potato ricer into a large bowl. Add the butter and half of the milk. Using a wooden spoon, incorporate gently until silky. Add the rest of the milk and more butter if you deem necessary. Rectify the seasoning.
Serve immediately as is, or push through the ricer again (if you’re going for that look) straight onto the serving plates.
