Homemade marshmallows are a total game changer—they taste nothing like the stuff that comes out of a plastic bag, and a single bite of one may alter your marshmallow-eating course forever. Despite the page-long instructions for this recipe, it’s a pretty straightforward process. Just be sure to exercise a bit of caution while pouring scalding-hot syrup down the side of the mixer bowl. That requires just a bit of concentration but, after you do it once, you’ll have the hang of it going forward.
MAKES ABOUT 8 CUPS MARSHMALLOW CREAM OR ABOUT 54 (2-INCH) SQUARE MARSHMALLOWS
SPECIAL EQUIPMENT
Candy thermometer, stand mixer
¾ cup (150 grams) granulated sugar
½ cup (180 grams) Lyle’s Golden Syrup (see Sources)
¼ teaspoon (1 gram) kosher salt
2 large egg whites, at room temperature
¼ teaspoon cream of tartar
1½ teaspoons pure vanilla extract
½ cup (80 grams) cornstarch, plus more as needed (optional, if spreading on a baking sheet)
½ cup (60 grams) confectioners’ sugar, plus more as needed (optional, if spreading on a baking sheet)
1. In a medium, heavy-bottomed saucepan, stir together the sugar, golden syrup, salt, and ¼ cup water until combined. Clip a candy thermometer to the pan and bring the mixture to a boil over high heat, stirring occasionally, until it reaches 240˚F on the candy thermometer.
2. Meanwhile, place the egg whites and cream of tartar in the bowl of a stand mixer fitted with the whisk attachment. Starting with the mixer on low and gradually increasing to medium-high speed, whip the egg whites until they hold soft peaks. (Be sure to have those whipped before the syrup is done.)
3. Once the syrup has reached 240˚F, remove it from the heat. With the mixer on low speed, slowly add 2 tablespoons of the syrup to the egg whites to temper them. Raise the mixer speed to medium and carefully drizzle in the remaining syrup, making sure that the syrup flows along and down the inside of the bowl (this will help cool the syrup before it reaches the egg whites). Raise the mixer speed to high and whip until the marshmallow cream is stiff and glossy, 4 to 5 minutes. Add the vanilla and whip for a minute more.
4. If making individual marshmallows, combine the cornstarch with confectioners’ sugar in a bowl, then sprinkle a generous layer of the mixture over a rimmed baking sheet. Using an offset spatula, spread the marshmallow cream evenly over the baking sheet, smoothing the sides, edges, and top. Sprinkle the remaining cornstarch-sugar mixture over the top and let the marshmallow dry overnight at room temperature before cutting into 2-inch squares. You may need more cornstarch-sugar mixture to coat the individual pieces once they’ve been cut. Use immediately in S’Mores or cover and refrigerate for up to 2 weeks.
ben’s note For cutting marshmallows into individual pieces, kitchen shears dipped in a cornstarch–confectioners’ sugar mixture work best.