Whip sugar and egg whites together in a double boiler until the temperature reaches 120 degrees F, on an instant-read thermometer, and sugar is dissolved. Transfer to the bowl of a stand mixer, whip to soft peaks and add butter, a little at a time, until incorporated and fluffy.
This recipe was provided by professional chefs and has been scaled down from a bulk recipe provided by a restaurant. The Food Network Kitchens chefs have not tested this recipe, in the proportions indicated, and therefore, we cannot make any representation as to the results.
Recipe courtesy of Bronwen Weber
Recipe courtesy of Ron Ben-Israel