Begin by peeling and chopping about 2 pounds of starchy potatoes, like Russets. Place them in a large pot of salted water and bring it to a boil over medium-high heat. Cook the potatoes for 15–20 minutes until they are tender and can be easily pierced with a fork.

Return the drained potatoes to the pot and mash them until smooth and creamy, free of lumps. Add in one beaten egg, 4 tablespoons of butter, and ½ cup of grated Parmesan cheese, stirring until well combined. Season with salt and pepper.

Fill a piping bag fitted with a star-shaped nozzle with the potato mixture. On a parchment-lined baking tray, pipe spiral shapes approximately 3 inches in diameter, leaving a well in the center of each for the filling.

Into the wells of each potato nest, add cubes of Swiss cheese and diced thick-cut bacon, ensuring an even distribution. Sprinkle additional grated Parmesan cheese on top if desired.

Preheat your oven to 375°F (190°C). Place the baking tray in the oven and bake the nests for about 20 minutes or until golden brown and crispy on the outside.

Once baked, remove the nests from the oven and let them cool for a few minutes. Garnish with chopped fresh herbs and serve.