Boil the potatoes whole until they are tender when poked with a fork.
Let the potatoes cool slightly then peel.
Pass the potatoes through a food mill or grate on a cheese grater into a large mixing bowl.
Add the egg, butter, flour, salt and nutmeg into the potatoes and mix just enough to combine all the ingredients.
Divide the dough in two. Cover half the dough with a tea towel and roll the other half of the dough on a floured surface into a finger-width rope.
Cut the rope of dough into 1-inch pieces and place them on a floured baking sheet.
Roll and cut the other piece of dough.
Bring a large pot of salted water to a boil.
Place the gnocchi into the water and wait for about 3 minutes for them to cook. Once the gnocchi starts to float scoop them out of the pot with a slotted spoon and into your sauce.
Once all of the gnocchi have been scooped out of the pot, toss them with the sauce, garnish with parmesan and fresh parsley and serve.