Royal Icing with Meringue Powder. But sometimes I'll get questions about making royal icing with egg whites instead of the powdered version.
What You Need
3-4 egg whites (about 1/2 cup)
2 Tbsp. granulated sugar
1 tsp. vanilla
4-5 cups powdered sugar
Set the bowl over simmering water, and whisk constantly until the egg whites reach the food-safe temperature of 160-degrees. (Be careful to keep the heat low, or the whites can cook.)
Add 4 cups of powdered sugar. Mix on high speed with a hand or stand mixer for 4-5 minutes or until stiff peaks form. If icing seems runny, and won't form a stiff peak, try adding another 1 cup of sugar. (If it requires more than one more cup, you may have gotten grease in the icing, and it won't set up, regardless of how much sugar you add.)
Compare this photo above with the one above it... you can see the difference.
Store royal icing in an airtight container. (I usually store it in zipper baggies so that no air comes into contact with it.)
*Note: I'm having some of the white icing turn yellow in the sunlight... I will update if/when I figure out a cause. In the meantime, if you need it to stay white, you may try white icing coloring or just be sure to keep it out of the sunlight.
Click the Links Below to See:
Royal Icing Recipe and Tips
Royal Icing Consistency
Cookie Decorating Ideas
Gingerbread House Recipe and Tips