Duchess Potatoes

Ingredients

• 0.3 teaspoon pepper black freshly ground
• 6 large egg yolk at room temperature
• 0.3 cup cup heavy whipping cream at room temperature
• 1 teaspoon kosher salt as needed plus more
• 0.1 teaspoon nutmeg freshly grated
• 2.5 pounds baking potatoes 
• 1 ounce swiss cheese shredded grated finely
• 6 tablespoons butter unsalted cut into 8 pieces, at room temperature ()

Equipment

• baking sheet
• sauce pan
• baking paper
• oven
• knife
• pot
• potato masher
• wooden spoon
• spatula
• colander
• potato ricer

Directions

1. Heat the oven to 400°F and arrange the racks to divide the oven into thirds. Line 2 baking sheets with parchment paper and set aside.Wash and peel the potatoes, cut them into 1-1/2-inch chunks, and place in a large saucepan. Cover with 1 1/2 to 2 inches of cold water and salt generously. Bring the potatoes to a boil over high heat. Reduce the heat to medium low and simmer until the potatoes can be easily pierced with a knife, about 15 minutes.
2. Drain in a colander. Return the potatoes to the pot and mash with a potato masher until very smooth. (Alternatively, use a potato ricer.)While the potatoes are still warm, mix in the egg yolks 1 at a time using a wooden spoon or rubber spatula, making sure each yolk is completely incorporated before adding the next.
3. Add the butter, cream, measured salt, pepper, and nutmeg and stir until the butter has melted and the mixture is smooth.
4. Transfer to a large piping bag fitted with a 1/2-inch star piping tip and pipe 12 round mounds (2 1/2 inches wide by 2 inches tall) onto each prepared baking sheet, spacing them about 2 inches apart.
5. Sprinkle with the cheese.
6. Place both sheets in the oven and bake for 15 minutes. Rotate the pans top to bottom and front to back and continue baking until the tops of the potatoes are light golden brown, about 10 minutes more.