Boil the potatoes in salted water until tender, about 20 minutes.
Drain and let them cool slightly, then peel.
Mash the potatoes until smooth and let cool completely.
In a large bowl, combine the cooled mashed potatoes with flour, egg, salt, and nutmeg.
Mix until a soft dough forms, adding more flour if necessary.
Divide the dough into 4 pieces for easier handling.
Roll each piece into a long rope, about ¾ inch thick.
Cut the ropes into 1-inch pieces and shape them with a fork.
Bring a large pot of salted water to a boil and add the gnocchi.
Cook until they float to the surface, about 2-3 minutes, then remove with a slotted spoon.