Buttermilk Mashed Potatoes with Chives

Serves 6, yields 5 1/2 cupsIngredients:3 pounds russet potatoes (4 to 6 medium), peeled and cut into 1 1/2 to 2 chunksKosher salt6 to 8 tablespoons unsalted butter, at room temperature, cut into 4 pieces1 cup buttermilk, at room temperature 1/4 cup thinly sliced chives 1 small bunch)Put the potatoes in a large saucepan and cover by an inch with cold water. Add 1 1/2 teaspoons kosher salt. Bring to a simmer over medium heat, partially covered, and simmer until the potatoes are tender and easily pierced with a skewer, about 20 minutes. Drain and return the potatoes to a saucepan. Put the pan over low heat, and shake or stir the potatoes until a floury film forms on the bottom of the pot, 1 to 2 minutes. Using a ricer, food mill, or potato masher, mash the potatoes. Stir in butter, 1 piece at a time, with a broad wooden spoon. Once the butter is absorbed, add the buttermilk in three parts, stirring vigorously between additions. Add chives and season with salt and pepper. Serve hot. If you need to keep potatoes warm before serving, place the potatoes in a large stainless steel bowl, cover tightly with plastic wrap, and place over a pan of simmering water. The potatoes can be held for an hour– just be sure that the bottom of the bowl sits above the surface of water and that the water doesn’t simmer away.