- 4 pounds russet potatoes
- 1 pound Yukon Gold potatoes
- 3 tablespoons kosher salt plus more to finish
- 1 cup whole milk
- 1/2 cup heavy cream
- 8 whole white peppercorns
- 3 sprigs thyme/rosemary/sage
- 2 bay leaves
- 1/2 cup (1 stick) chilled unsalted butter, cubed
- kosher salt and ground white pepper
Fill a large pot halfway with cold water. Peel potatoes and cut into 2″ pieces, adding to pot as they are cut. Add cold water to cover by 1″ if needed. Stir in kosher salt. Bring to a boil, then reduce heat to medium-low and gently simmer until tender, 10–15 minutes. Drain potatoes, transfer to a bowl, and mash with the butter.
Meanwhile, heat whole milk, heavy cream, peppercorns, fresh herbs, and bay leaves in a small saucepan over medium heat, stirring occasionally, until mixture is very hot but not boiling, about 10 minutes. Remove from heat and let mixture infuse for 20 minutes; strain. This will add herbal flavor without coloring the liquid.
Stir in the hot cream mixture. Season generously to taste with kosher salt and ground white pepper. To keep warm (warning: THIS IS GENIUS), press plastic wrap directly against the surface and set bowl over (not in) a large pot of simmering water for up to 2 hours.
Adapted from Bon Appetit