Peel and chop the potatoes into even chunks, place in a pot of salted water, bring to a boil, then simmer for 15-20 minutes until fork-tender. Drain and return to pot.

Preheat the oven to 425°F (220°C) and line a baking sheet with parchment paper.

Melt half of the butter over low heat, add the cream until it steams, then set aside.

Mash the potatoes until smooth, then mix in the melted butter and cream, Parmesan cheese, salt, pepper, and egg yolks until fluffy.

Transfer mixture to a piping bag; pipe small mounds onto the prepared baking sheet.

Brush each mound with remaining melted butter and bake for 15-20 minutes until golden brown.

Remove from oven, garnish with chives or parsley, and a sprinkle of sea salt before serving.