Gather all the ingredients and equipment. Ensure your egg whites are at room temperature.
In a heavy-bottom saucepan, combine the sugar, corn syrup, and water. Cook over medium heat, stirring until dissolved. Stop stirring and attach a candy thermometer. Boil until it reaches 240°F.
While the syrup cooks, whip the egg whites in a stand mixer. Start on low, then increase to medium. Add cream of tartar when frothy, and whip until soft peaks form.
Once the syrup reaches 240°F, pour it slowly into the egg whites with the mixer on low. Increase to high speed and whip until thick and glossy, about 6-8 minutes.
Add the vanilla extract and mix for an additional minute to incorporate.
Transfer the fluff to an airtight container and let it cool to room temperature before sealing.
