If you need to keep the potatoes warm before serving, create a makeshift double-boiler: Transfer the potatoes to a large stainless-steel bowl, cover tightly with plastic wrap, and place the bowl over a pan of simmering water. The potatoes can be held for about an hour this way-just be sure that the bottom of the bowl sits above the surface of the water and that the water doesn’t simmer away.
Yields 5 1/2 cups; serves 6
- 3 lb. russet potatoes (4 to 6 medium), peeled and cut into 1 1/2- to 2-inch chunks
- Kosher salt
- 6 to 8 Tbsp. unsalted butter, at room temperature, cut into 4 pieces
- 1 cup buttermilk, at room temperature
- 1/4 cup thinly sliced chives (1 small bunch)
- Freshly ground black pepper
- Put the potatoes in a large saucepan, cover by an inch with cold water, and add 1 1/2 tsp. salt. Bring to a simmer over medium heat, partially cover, and simmer until the potatoes are tender and easily pierced with a skewer, about 20 minutes. Drain, and return the potatoes to the saucepan. Put the pan over low hear, 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 the butter, 1 piece at a time, with a broad wooden spoon. Once the butter is thoroughly absorbed, add the buttermilk in 3 parts, stirring vigorously between additions. Add the chives, and season to taste with salt and pepper. Serve hot.