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

In a large pot, add cold salted water and the Yukon gold potatoes. Boil and cook until very tender, about 15-20 minutes. Drain well.

Melt 4 tablespoons of butter in a saucepan over medium heat, add minced garlic, and sauté until golden, about 1-2 minutes. Stir in 3 tablespoons of half and half.

Mash the drained potatoes until smooth, then incorporate the garlic butter mixture and finely shredded Parmesan cheese. Season with salt and black pepper.

Mix in the egg yolks and add remaining half and half if needed for smooth consistency.

Pour the potato mixture into a piping bag and pipe onto the prepared baking sheet, or spoon them directly.

Bake for about 16-19 minutes or until golden brown and slightly crisp.

Let cool slightly before garnishing with minced parsley and additional grated Parmesan.