Sugar Cookie Icing Recipe: Professional Royal Icing That Hardens

Instructions:

1. Sift Dry Ingredients: In the stand mixer bowl, combine and thoroughly whisk the sifted icing sugar, meringue powder, and salt to prevent lumps.
2. Add Wet Ingredients: Pour the measured water and vanilla extract directly into the dry mixture.
3. Combine on Low: Attach the paddle and mix on the lowest speed until the ingredients are just combined into a shaggy paste (about 30 seconds). Scrape down the sides of the bowl.
4. Whip to Stiff Peaks: Increase the speed to medium-high and beat vigorously for 5 to 7 minutes until the icing thickens, turns glossy white, and forms stiff peaks. This is the Piping and Outlining Consistency.
5. Cover Immediately: Transfer the Piping Consistency icing to an airtight container or cover the bowl tightly with plastic wrap pressed directly onto the surface to prevent crusting, as royal icing dries instantly.
6. Divide and Colour: Divide the piping consistency icing into separate bowls and mix in gel food colour carefully. Use only gel coloring, as liquid colours compromise stability.
7. Create Flooding Icing: For filling, thin the designated icing by adding water, one teaspoon at a time, mixing well after each addition.
8. Test Consistency (10-Second Rule): Run a knife through the thinned icing. The ribbon track should take approximately 8–10 seconds to smooth completely back over. Adjust consistency as necessary.
9. Bag the Icing: Transfer the piping consistency icing into bags for outlining, and the flooding consistency icing into bottles or separate bags for filling.
10. Decorate: Pipe a defined outline onto the cookie using the thicker icing and allow it to set for 10 minutes. Then, fill the outlined area quickly with the thinner flooding consistency. Use a scribe tool to pop bubbles.
11. Dry: Allow the finished decorated cookies to dry flat and undisturbed for 6–8 hours, or preferably overnight, for a hard, transport-ready finish.