Put the potatoes and 1 cup water in a pressure cooker. Cover and cook on high for 5 minutes.
Peel the potatoes while still hot. Pass the potato flesh through a ricer set over a large bowl.
Meanwhile, in a large pot over high heat, bring 6 quarts salted water to a boil. Line a baking sheet with a lightly floured kitchen towel or paper towels.
Mound the potatoes on a lightly floured work surface and make a well in the center. Pour the eggs into the well. Season the potatoes with salt, nutmeg and white pepper. Sprinkler 1 cup of the flour over the potatoes. Using a fork, gradually blend the eggs with the potato mixture. Using your hands, mix the dough, adding more flour as needed to for a firm but moist dough; do not overwork. The mixing process should take no more than 5 minutes.
Divide the dough into 6 equal pieces. Roll each piece into a rope about ¾ inch thick, flouring the work surface as needed so the dough is not sticky. Cut each rope into 1-inch pieces and gently roll each piece on a gnocchi ridger. Place the gnocchi on the prepared baking sheet.