1. Place the peeled and cut Yukon Gold potatoes in a large pot and cover them with cold water. Add a pinch of salt to the water. Bring to a boil over medium-high heat, then reduce to a simmer and cook until the potatoes are fork-tender, about 15-20 minutes.
2. While the potatoes cook, melt the unsalted butter in a small saucepan over medium heat. Keep a close eye on it, stirring occasionally. The butter will foam and then begin to turn golden brown with a nutty aroma—this usually takes about 5-7 minutes. Once browned, remove from heat immediately to avoid burning. Set aside.
3. Optional: In a separate small saucepan, warm the whole milk with the smashed garlic cloves until steaming. Remove the garlic cloves and discard. This technique infuses a subtle garlic flavor without overpowering the dish—one of my mother Elena’s favorite tricks for adding depth.
4. Drain the cooked potatoes thoroughly and return them to the warm pot. Using a potato masher or ricer, mash the potatoes until mostly smooth but still a bit rustic, like Nonna Rosa liked them.
5. Slowly stir in the warm milk, mixing gently to keep the potatoes fluffy. Add the browned butter in a steady stream while stirring, allowing the golden richness to coat every bite.
6. Season with kosher salt and freshly ground black pepper. Taste and adjust seasoning as needed.
7. Transfer to a serving bowl and garnish with fresh chives or parsley if desired. Serve warm and enjoy the comforting, buttery goodness.

One tip I’ve learned from my travels across Italy is to never rush the browning of butter—it’s a delicate process but worth the patience. The aroma alone will have your whole kitchen smelling like a cozy trattoria.