Begin by peeling and chopping 2 pounds of Russet or Yukon gold potatoes into equal-sized pieces. Place them in a large pot of salted water and bring to a boil. Cook for 15 to 20 minutes or until fork-tender; drain thoroughly and return to the pot.

While the potatoes are cooling slightly, preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper.

In a small saucepan, melt 2 tablespoons of unsalted butter over low heat. Once melted, add in 1/4 cup of heavy cream, warming it gently without boiling. Set aside the butter-cream mixture.

Drain any remaining water from your potatoes and return them to the warm pot. Using a potato masher, mash the potatoes until completely smooth. Mix in the melted butter, warm cream, 1/4 cup grated Parmesan cheese, 1 teaspoon salt, and 1/2 teaspoon black pepper. Combine thoroughly.

Transfer the potato mixture into a piping bag fitted with a star tip. Pipe small mounds onto the prepared baking sheet, spacing them about two inches apart.

Brush the piped potatoes with any leftover melted butter and place the baking sheet in the preheated oven. Bake for 15 to 20 minutes.

Once baked, remove the Duchess Potatoes from the oven and let them cool for a minute. Finally, sprinkle with fresh chopped chives or parsley and a dusting of sea salt before serving warm.