Make it ahead: refrigerate the mashed potatoes for up to 2 days. To reheat, place ina double boiler or glass bowl set over (but not in) simmering water, adding whole milk as necessary to adjust consistency until heated through, 15-20 minutes

ready in about 50 minutes; serves 8
You might need to buy:
  • Kosher salt
  • half and half
  • unsalted butter
  • small sprigs rosemary
  • black peppercorns freshly grated or ground nutmeg for serving