Photo, Roberto Caruso.
Decorating cookies? Royal icing is perfect for a neat and beautiful design. (And very easy to make — you only need three ingredients!)
3 egg whites
1/4 tsp white vinegar
5 cups icing sugar, sifted
BEAT egg whites and vinegar until foamy in a large bowl using an electric mixer. Add icing sugar and mix until combined. Increase speed to high and beat until dense and thick but foamy, about 3 to 7 minutes.
STIR in 2 to 4 tbsp cold water to thin the icing out to desired consistency. Transfer to a piping bag fitted with a very small plain tip to decorate cooled sugar or gingerbread cookies. If applying silver dragees or other decoration, do so while icing is still wet. Let sit at room temperature until royal icing hardens.
Try this royal icing recipe out on one of our classic gingerbread cookies.