Start by adding unsalted butter to a medium saucepan over medium heat. Allow the butter to melt and stir continuously until it turns golden brown, about 5-7 minutes. Remove from heat and let cool slightly.

While your brown butter cools, peel and quarter the potatoes. Place them in a large pot filled with salted water and bring to a boil over high heat. Cook until fork-tender, about 15-20 minutes. Drain the potatoes and return them to the pot to steam dry for a minute.

With the potatoes still hot, add hot whole milk and mash until mostly smooth, then incorporate the cooled brown butter until silky and lump-free.

Season with salt to taste, transfer to a serving dish, and serve warm with a pat of butter on top.