Marshmallow Fluff

Gather the ingredients.

Fill a small pot halfway with water and bring to a boil. Combine the egg whites, sugar and corn syrup in the stand mixer bowl. Whisk to mix.

Set the bowl over the pot with boiling water. Whisk constantly, keeping water at a vigorous simmer until the sugar is completely dissolved into the egg whites, and they reach 160 F, using an instant read thermometer to test, 4 to 5 minutes.

Affix the bowl to the stand mixer with the whisk attachment in place. Add the vanilla extract and cream of tartar. Starting on low and gradually increasing the speed to high, beat the whites until they form a glossy, sticky meringue-like marshmallow cream, with stiff peaks that cling to the whisk attachment without slipping off, 5 to 6 minutes.

Store in a covered container in the refrigerator for up to 2 weeks. Use as a frosting, filling for cupcakes or as you would any recipe calling for marshmallow cream.