¼teaspoongrated nutmegwhole nutmeg, grated with a Microplane
½teaspoonkosher salt+ more to taste
Instructions
Preheat oven to 400℉ (200℃). Line a rimmed sheet pan with foil.
Wash, dry, and prick the sweet potatoes several times with a fork and place them on the rimmed sheet pan. Roast the sweet potatoes for 45-60 minutes, or until the flesh is completely soft and a fork goes through easily. Let the sweet potatoes rest until cool enough to handle. I let them sit while I brown the butter.
While the sweet potatoes cool, melt 4 tablespoons unsalted butter in a small saucepan over medium heat, stirring constantly. It will foam at first; the foam will subside, and then little browned bits will begin to sink to the bottom as the butter bubbles. Remove from the heat IMMEDIATELY once the butter smells nutty and is deep, golden brown. This will take anywhere from 3-8 minutes.
Then remove and discard the skin from the sweet potatoes, and place the flesh in a food processor fitted with an S-blade.
Add the browned butter, ¼ cup pure maple syrup, 1 teaspoon vanilla extract, 1 teaspoon ground cinnamon, ¼ teaspoon grated nutmeg, and ½ teaspoon kosher salt (omit if using salted butter) to the sweet potatoes, then process until smooth and creamy. Taste and add more salt if needed.
Transfer the sweet potatoes to a serving dish and serve immediately OR transfer to a 2-quart baking dish, cover with foil, and keep warm in a 250℉ oven for up to 2 hours.
Video
Notes
Sweet Potatoes: For 3 pounds, you will need about 3 large or 6 medium; weigh for best results.Butter: If using salted butter, omit the added salt and add to taste. You can also skip the browning and use melted butter. Good, but the nutty browned butter takes it from good to exceptional.Brown Sugar: Swap the maple syrup for ¼ cup brown sugar. The mash will be a bit thicker, but perfectly sweet.No Food Processor? Use a handheld or stand mixer to whip the sweet potatoes with the remaining ingredients. Storage: Store leftovers in an airtight container in the fridge for up to 4 days or freeze for up to 3 months. To reheat, let thaw in the fridge overnight if needed. Then reheat in a microwave-safe dish, covered with a damp paper towel, in 60-second intervals until warmed through, stirring between intervals.