International
Peel the potatoes and cut them into even chunks of about 5 cm.
Put them in a pot, cover with cold water by 2 cm, add 1 tsp of the salt and bring to a boil.
Simmer, partly covered, for 18-20 minutes, until a knife slides into the chunks without resistance.
Meanwhile, heat the milk with the butter until the butter melts; do not let it boil.
Drain the potatoes well, return them to the hot pot and let them steam dry over low heat for 1 minute.
Mash with a potato masher until no lumps remain, then beat in the hot milk and butter a little at a time.
Season with the remaining 1 tsp salt and the pepper and serve hot.