for 4 servings
yukon gold potato(1.8 kg)
kosher salt, plus more to taste
unsalted butter, 1 stick, melted (115 g)
heavy cream(240 mL)
2 sprigs fresh rosemary
1 head garlic, crushed
butter, for serving
freshly ground black pepper, to taste
chives, finely chopped, for serving
gravy, for serving
On a cutting board, peel the potatoes. Place the potatoes in a large bowl of cold water after peeling to prevent discoloration.
Dice the potatoes into 1-inch (2-cm) cubes.
Add the potatoes to a large pot of cold water, along with the salt. Bring to a soft boil over high heat, then reduce the heat to low and simmer for about 12 minutes, until the potatoes are fork-tender.
Drain the potatoes in a colander, then return to the pot. Increase the heat to medium-high and stir the potatoes around for 2-3 minutes to evaporate any excess moisture.
Transfer the potatoes to a large bowl and mash with a potato masher, potato ricer, or by pushing through a fine mesh sieve with a spatula.
Add the melted butter and stir to incorporate, then season with salt to taste.
In a small saucepan, combine the heavy cream, rosemary, and garlic. Bring to a simmer over low heat, let simmer for a few minutes, then remove the pot from the heat and strain through a fine mesh sieve.
Gradually add the cream mixture to the potatoes, a little at a time, stirring until fully incorporated.
Top with a pat of butter, freshly ground black pepper, and a sprinkle with chives, or gravy, if desired.