Why It Works
- Drying the cooked potatoes in a pot on the stovetop removes excess moisture, allowing for richer, creamier potatoes.
- Enriching mashed potatoes with egg gives them structure, allowing them to hold their shape when piped.
- The recipe is calibrated to make both individual piped portions or an attractive casserole, allowing you to choose a preferred serving presentation.
Have you ever found yourself staring at a mound of mashed potatoes, perhaps nestled alongside a perfectly seared steak or jostling for room on an overfilled holiday plate, and thought, “I love my grade-school gravy moat, but there has to be a fancier, fussier, French-ier way of plating these spuds”? If you answered yes, and aren’t already familiar with pommes duchesse, then it’s time to get acquainted. Duchess potatoes are classic old-school French cuisine: riced boiled potatoes, mounted with egg yolks and butter, and seasoned with nutmeg. This mixture could be used as a base for other potato preparations such as pommes dauphine, which incorporates pâte à choux for airy fried potato puffs, or stuffed into a pastry bag fitted with a decorative star tip, then piped and baked into pretty individual portions of rich mashed potato.
To be clear, aesthetics aren’t the only draw of pommes duchesse. The addition of eggs adds structure that allows the potatoes to hold their shape when piped, it also lends them extra richness. For this recipe, I settled on a combination of two yolks plus one whole egg, which, when baked, help the potatoes puff up, their surface browning and crisping slightly, producing a thin shell of sorts that contrasts nicely with the creamy mashed potato interior. It’s like a cross between a savory mashed potato soufflé and meringue.
Piping individual portions of potato may seem a little much for some people, and I don’t disagree. But sometimes you want to pull out all the stops at a dinner party or holiday gathering, and this is the perfect recipe for those occasions. I developed the recipe to work for making either individual piped portions or a slightly more rustic, but still eye-catching, family-style casserole. To maximize creaminess without compromising on structural integrity, I add a touch of heavy cream to the mixture along with the traditional eggs and butter.
Yukon Golds produce the silkiest, and most full-flavored duchess potatoes, but russets work fine as well. An optional light coating of clarified butter promotes browning in the oven, but there’s enough fat in the potato mixture already to get good results without it. When you want to impress, go with duchesse.
- 3 pounds (1.4kg) Yukon Gold potatoes, peeled and cut into 1-inch pieces (see note)
- Kosher salt and freshly ground black pepper
- 1/3 cup (80ml) heavy cream
- Pinch freshly grated nutmeg
- 6 tablespoons (90g) unsalted butter, melted
- 1 large egg plus 2 yolks, lightly beaten
- Nonstick cooking spray (for piped individual portions only)
- Melted clarified butter, for brushing (optional)
Adjust oven rack to middle position and preheat oven to 450°F (230°C). In a medium pot, combine potatoes, 2 quarts cold water, and 2 teaspoons salt. Bring to a boil over high heat, then reduce heat to maintain a simmer. Cook until potatoes are tender and offer little resistance when pierced with a paring knife, about 10 minutes. Drain potatoes, then return to now-empty pot.
Set pot over low heat and cook, shaking constantly, until moisture has evaporated from potatoes, 30 seconds to 1 minute. Remove from heat.
Using a ricer or food mill, pass potatoes into a medium bowl. Using a flexible spatula, stir in butter. Once butter is fully incorporated, stir in cream and nutmeg. Season with salt and pepper to taste. Stir in beaten egg mixture until combined, taking care not to over-mix the potatoes.
For Individual Portions: Line a rimmed baking sheet with parchment paper and grease lightly with nonstick cooking spray. Transfer potato mixture to a pastry bag fitted with a 1/2-inch star tip. To pipe the potatoes, hold the filled pastry bag at an 80° angle, apply steady downward pressure, and pipe a 3-inch-wide mound, working in a circular motion. To stop piping, cease applying pressure and swirl the pastry tip away. Continue to pipe portions about 2 inches apart, for a total of 12 portions. Lightly coat portions with clarified butter (if using), taking care not to undo the piped design.
For a Casserole: Grease a 2-quart baking dish, then set it on a rimmed baking sheet. Transfer 2/3 of potato mixture to prepared baking dish. Transfer remaining 1/3 to a pastry bag fitted with a 1/2-inch star tip. Using a flexible or offset spatula, smooth potato mixture in baking dish in an even layer. Pipe remaining potato on top by holding filled pastry bag at an 80° angle, and applying steady downward pressure to form small mounds in an even decorative pattern. Lightly coat portions with clarified butter (if using), taking care not to undo the piped design.
Transfer to oven and bake until golden brown, 15 to 20 minutes for individual portions, and about 25 minutes for a casserole; rotating baking sheet halfway through baking. Serve.
Ricer or food mill, disposable pastry bag, 1/2-inch star tip, rimmed baking sheet, 2-quart baking dish (optional)
We feel that creamy full-flavored Yukon Golds make the best duchess potatoes, but russets also work for this recipe. Duchess potatoes made with russets have a fluffier and slightly drier interior; if you want the texture to be closer to the Yukon Gold version, add 1 to 2 tablespoons more cream to the potato mixture in step 3.
Make-Ahead and Storage
The potato mixture can be prepared through step 4, and the baking sheet of piped portions or casserole can be covered and refrigerated overnight. Allow potatoes to sit at room temperature for at least 30 minutes before baking.