Peel potatoes and cut into chunks about 2 inches in size. Place in large pot of salted water (at least 1 teaspoon of salt in the water) and boil 15 minutes or until potatoes break easily when pierced with a fork.
Drain potatoes well but leave them in the pot.
Add hot milk, beginning with the smaller amount. Add butter. Mash with potato masher and add more milk, butter, salt and pepper if necessary to suit your taste.