- 10 (4-inch-long) Yukon gold potatoes, rinsed under cool water
- 1 cup whole milk, warm
- 6 Tbsp. unsalted butter
- 2 scallions, chopped
- 2 tsp. kosher salt
- Cracked pepper
- Lemon zest for garnish
Since the potatoes take some time to boil, mash, and whip, and then the pots and bowls have to be cleaned, I make my mashed potatoes 4 to 5 hours before I need to serve them. I keep them fluffy and warm by using the double boiler method. I place my mashed potatoes in a ceramic, Pyrex, or stainless-steel bowl on top of a pot filled with water 1/3 of the way up that has been brought to a boil, then turned down to a low simmer. Make sure the pot with the mashed potatoes doesn’t sit in the water. It should fit snugly on top of the pot. Keep the potatoes covered. Check the water level every hour or so to make sure there is enough to keep the simmer going. Before you serve the potatoes, use a large spoon to turn the potatoes on the bottom and bring them to the top. If you use this method, add the chopped scallions at the last minute before you serve.
Place the potatoes in a large pot and fill with water to cover the potatoes by 2 inches. Bring to a boil; then lower the heat to a gentle boil. Cook until the potatoes are tender, about 30 minutes. Test for doneness by gently inserting a paring knife through the middle. If it goes in smoothly, your potatoes are done.
Drain under cool running water and transfer to a bowl. Gently peel off the skins and discard. Run the hot potatoes through a potato ricer over a large pot (the same pot you boiled the potatoes in is fine). (If you don’t have a ricer, use a potato masher; the potatoes come out creamier if you use a ricer.)
Place the pot on the stove over medium heat and add ½ cup of the warm milk and half of the butter. Mix well until the butter has melted. Add the other ½ cup of milk, the rest of the butter, the scallions (if you are making the potatoes in advance, don’t put the scallions in at this point; wait until you are ready to serve), and the salt. Mix well, turning constantly. Taste and add more salt if needed.
Serve in a warmed bowl. Add 1 tablespoon of softened butter, if you wish, crack some fresh pepper on top, and sprinkle on lemon zest.