Boil the potatoes, then mash,
measure them and use 2 cups.
(Save remaining potatoes for another use).
Add the butter and milk to the potatoes while still hot.
Whisk until light and fluffy.
Add a little more butter and milk if the mixture is too stiff.
Season with salt, pepper and nutmeg.

Blend in lightly beaten egg yolks
and fold in the stiffly beaten egg whites.
Spoon mixture into a souffle dish, sprinkle with Parmesan,
bake at 375° for about 20 min. Serves 4.