Ingredients:
- 3 cups powdered sugar (360g), sifted
- 2.5 tablespoons whole milk
- 2 tablespoons light corn syrup
- 1 teaspoon vanilla extract
- 1 pinch fine sea salt
- Gel food coloring (as needed)
Instructions:
- Place your sifted powdered sugar into a large mixing bowl. Add the milk, corn syrup, vanilla, and salt.
- Stir the mixture slowly until the sugar is fully hydrated. If the icing is too stiff, add more milk 1/2 teaspoon at a time until it reaches a thick, glue-like consistency.
- Perform the 10-second consistency test: Lift the spatula and let the icing drip back into the bowl. The trail should disappear into the surface in exactly 10–12 seconds.
- Divide the icing into bowls and mix in gel food coloring. Transfer to piping bags or squeeze bottles to outline and flood the cookies.
- Allow cookies to sit on a flat surface for 6 to 12 hours (ideally overnight) to harden completely for stacking.