Ingredients:

  • 4 cups confectioners' (icing) sugar, packed
  • 3 tablespoons meringue powder
  • 6-8 tablespoons lukewarm water, divided
  • 1 teaspoon clear vanilla extract
  • Pinch of fine sea salt

Instructions:

  1. Sift the confectioners' sugar and meringue powder together into the bowl of a stand mixer. This step is mandatory for a smooth finish.
  2. Add 6 tablespoons (90 ml) of lukewarm water, the vanilla extract, and the pinch of salt to the dry ingredients. Mix on the lowest speed for 30 seconds until just combined, then scrape down the bowl.
  3. Increase the speed to medium (4-5) and beat for 5–7 minutes. The icing should become thick, opaque white, and hold stiff peaks. If too dry, add the remaining water one teaspoon at a time.
  4. Transfer the stiff base icing immediately to an airtight container and cover the surface directly with cling film to prevent crusting.
  5. Divide the stiff icing into smaller bowls for colouring, using only concentrated gel or paste food colouring.
  6. For Piping Icing (Outline/Detail): Use the stiff portion immediately. It should hold its shape perfectly when piped.
  7. For Flooding Icing (Fill): To the remaining icing, gradually add water one teaspoon at a time, stirring well after each addition.
  8. Test the flooding consistency using the '10-Second Rule': a drizzle should disappear back into the surface within 8–12 seconds. Adjust with more water (if too slow) or sifted sugar (if too fast).
  9. Outline the cookie designs using the stiff piping icing. Allow the outline to set for 10–15 minutes.
  10. Fill the outlined areas with the thinner flooding icing. Use a toothpick to spread gently to the edges and pop any surface air bubbles.
  11. Allow decorated cookies to dry completely, ideally for 12–24 hours, until the surface is rock hard and stackable.