Sugar Cookie Icing that Hardens
Sweet, glossy, and perfectly firm, this sugar cookie icing hardens to a beautiful, stackable finish. With just powdered sugar, corn syrup, milk, and vanilla, you’ll get the classic Christmas-cookie bakery sheen—no messy fingers and no soft, sticky cookies. Customizable for color or consistency, it’s the icing your holiday cookies deserve.
Equipment
- Mixing bowl
- Whisk
- Sifter or Fine Mesh Strainer
- Spoon or Spatula
Ingredients
Sugar Cookie Icing
- 2 cups confectioners' sugar sifted; also called powdered sugar
- 2 tbsp light corn syrup
- 2-3 tbsp milk or water plus more as needed for consistency
- 1 tsp vanilla extract
- gel food coloring as desired, for color
Instructions
- Sift the confectioners' sugar into a bowl to avoid lumps and ensure a smooth icing.
- Add the corn syrup, vanilla extract, and 2 tablespoons of milk or water to the bowl. Stir vigorously with a whisk or spoon until the icing is smooth and glossy.
- Check the consistency: You want it thick but drizzly—if needed, add more milk or water, a few drops at a time, until you can drizzle the icing in ribbons that sit briefly on the surface before sinking in.
- If coloring, divide icing into separate bowls and tint each portion with a small amount of gel food coloring. Stir well and adjust until you reach your desired shade.
- Decorate completely cooled sugar cookies by spreading or piping the icing as you like. Add sprinkles or sanding sugar while icing is wet if desired.
- Let the decorated cookies set at room temperature until dry and firm, about 6-8 hours or overnight, before stacking or storing.
Notes
Storage: Store leftover icing in an airtight container in the fridge for up to 1 week. Press plastic wrap directly onto the icing's surface to prevent a sugar crust. Stir and add a splash of milk/water to loosen before using again.
Freezing: Transfer icing to freezer-safe bags or containers, removing air. Thaw in the fridge and stir well before using. Decorated cookies can be frozen once the icing is fully set.
Variations: Try adding a dash of lemon juice instead of vanilla for a citrus twist, or a little almond extract for a nutty flavor. Plant milk works great. Swap light honey or glucose syrup if you’re out of corn syrup—but note the set may vary slightly.
Nutrition
Calories: 55kcalCarbohydrates: 13gSodium: 1mgPotassium: 1mgSugar: 13gCalcium: 2mg
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