Fried Duck Fat Potatoes and Sage
The Williams Sonoma Test Kitchen chefs borrowed a genius French cooking technique for this holiday side dish—cooking potatoes with melted duck fat to add rich flavor and help them crisp up beautifully. Our recipe calls for a three-step cooking process: First the potatoes are baked low and slow in the oven, then they’re fried twice—once in canola oil and again in butter along with fresh sage leaves. After baking in the oven, the potatoes will need to be refrigerated for at least 8 hours or preferably overnight, which gives you a jump-start on the prep. Serve them for a holiday dinner alongside our Warm Spiced Crispy Porchetta with Oranges.
Ingredients
- 5 lb. (2.5 kg) russet potatoes, peeled and sliced paper-thin lengthwise on a mandoline
- 1/2 cup (4 fl. oz./125 ml) melted duck fat
- Kosher salt and freshly ground pepper
- Canola oil for frying
- 8 Tbs. (1 stick) (4 oz./120 g) unsalted butter, cut into 1/2-inch (12-mm) pieces
- 25 fresh sage leaves
Directions
Preheat an oven to 300°F (150°C). Line a 9-inch (23-cm) square baking dish with parchment paper, letting it overhang on all sides by at least 2 inches (5 cm).
In a large bowl, combine the potatoes, melted duck fat, 1 Tbs. salt and about 10 generous grindings of pepper. Using your hands, toss the potatoes, coating all of the slices.
Layer the potatoes in the prepared baking dish, alternating the direction you lay the slices for each layer. After all of the potatoes are layered in the dish, press down slightly. Cover the potatoes with a sheet of parchment paper, then cover tightly with aluminum foil. Bake until the potatoes are very tender, about 2 1/2 hours.
Transfer the baking dish to a wire rack and let cool for 10 minutes. Remove the foil but keep the parchment in place. Set a second 9-inch (23-cm) square baking dish on top. Weight the dish down evenly with unopened cans of beans or other heavy objects that fit in the dish and provide evenly distributed weight. Let cool at room temperature for 2 to 4 hours, then transfer the weighted-down potatoes to the refrigerator for at least 8 hours, ideally overnight.
When ready to fry, remove the cans, the second baking dish and the top parchment sheet. Using the overhanging parchment, lift the potatoes out of the dish and place on a cutting board. Trim the sides to create even straight lines, cutting off about 1/2 inch (12 mm) from each side, then cut the potatoes into 2-inch (5-cm) squares.
In a large cast-iron fry pan over medium-high heat, pour in oil to a depth of about 1/4 inch (6 mm). Working in batches, cook the potato squares on all sides, turning as needed, until golden brown, about 4 minutes total. Transfer to a paper towel–lined plate to drain. Wipe the pan clean.
In the same pan over medium-high heat, melt 4 Tbs. (2 oz./60 g) of the butter. Add half of the potatoes and then half of the sage leaves. Cook, basting the potatoes with the butter and sage, until the leaves are darkened and crisp, about 1 minute. Transfer to a paper towel–lined plate and sprinkle with salt. Wipe the pan clean. Repeat with the remaining 4 Tbs. (2 oz./60 g) butter, potatoes and sage leaves.
Transfer the potatoes and sage leaves to a serving bowl and serve immediately. Serves 8 to 10.
Williams Sonoma Test Kitchen