Wash and peel the potatoes and cut them into even sized chunks. Cook in salted water until tender.
When the potatoes are tender, tilt the lid of the pan and pour off the water. Return to a gentle heat and with the lid half on continue cooking for 2 or 3 minutes until the potatoes are dry.
Add the butter (as much as you like) and either crush the potatoes with a fork or a potato masher. Press them down firmly and pour over 0.25 pint of boiling milk which is enough for 1.5 to 2 lbs of boiling potatoes.
Do not stir yet. Instead put the lid on the saucepan and let stand in a warm place until the main coarse is dished up. Just before sering beat the potatoes well with a wooden spoon until they are light and fluffy.
Cut the potatoes into even sized pieces. Take care to cook the potatoes in water and not let the water boil away.
Do not stir the mixture until ready to serve.