Cook the potatoes in a large pot of salted water until they are tender.
Drain, peel, and mash them through a fine sieve.

Pour the mashed potatoes into a saucepan over medium heat and dry them for 2 to 3 minutes, stirring constantly.
Add the butter, egg, and egg yolks, then season with salt, pepper, and nutmeg to taste. Mix well.

Preheat the oven to 400 F (200 C).
Line a baking sheet with parchment paper or a silicone mat.
Pour the mashed potatoes into a piping bag fitted with a star tip and create small mounds, moving in a circular motion.
Sprinkle with Cayenne pepper to taste, then bake for 10 to 15 minutes.