Procedure: Boil potatoes in salted water until tender. Drain and immediately return to the pot they cooked in and put them over the burner they cooked on so they may dry out over the heat.
While still warm, mash the potatoes, blending in the butter, nutmeg, salt and pepper. Mash in the egg yolks, blending until completely absorbed.
Transfer the duchesse mixture to a piping bag fitted with a large star tip. Pipe single-portion-size spirals onto a baking sheet pan. Bake at 375°F until the edges are golden brown, approximately 8-10 minutes. Serve immediately.