5 pounds white or Yukon gold potatoes, peeled and cut into 2-inch pieces
Kosher salt and pepper
8 tablespoons (1 stick) unsalted butter, cut into pieces
3/4 cup buttermilk
1/4 cup heavy cream
1/4 teaspoon ground nutmeg
How to Make It
Place the potatoes in a large pot and cover with cold water. Bring to a boil and add 2 1/2 tablespoons salt. Reduce heat and simmer until just tender, about 15 minutes. Drain the potatoes and return to the pot. Add the butter, buttermilk, cream, nutmeg, 1/2 teaspoon salt, and 3/4 teaspoon pepper. Mash the potatoes with a handheld masher. Transfer to a serving dish.
Make-Ahead Note: The potatoes can be made up to 2 hours in advance and kept warm in a double boiler or Crock-Pot. If the potatoes are chilled and then reheated, they will turn dry and pasty.