|Egg white||1 Large|
|Cream of tartar||1⁄8 Teaspoon|
|Powdered sugar||1 1⁄2 Cup (24 tbs)|
In a deep bowl with a mixer on high speed, whip egg white, cream of tartar, and 1 teaspoon water until frothy.
Add powdered sugar, mix, then beat on high speed until mixture is very stiff but still spreadable, 5 to 8 minutes.
Use, or cover airtight and store at room temperature up to 8 hours; to prevent drying, keep covered except when using.