- 1 lb (16 oz) confectioner’s sugar
- 4 teaspoons powdered egg whites
- 1/3 c. water
- 1 T. fresh lemon juice
- 1 t. pure vanilla extract
- With an electric mixer, beat together all ingredients at medium speed until just combined, about 1 minute.
- Increase speed to high and continue to beat until icing holds stiff peaks, about 3 minutes if using a stand mixer and 10 minutes with a hand held.
- Use within one day.
- Using a small spatula or table knife spread thin layer of icing atop each cookie.
- If using colored decorations, sprinkle over cookies before icing sets.
- Let decorated cookies stand until icing sets, about 1 hour.
- Store cookies in single layers between sheets of parchment paper in an airtight container.