Need an easy, back pocket recipe for sugar cookie icing? Learn how to make cookie frosting that hardens into a glossy, shiny glaze coating. This kid-approved recipe uses four simple ingredients (with no meringue powder!), takes five minutes to make, and makes decorating a breeze for all ages.

a yellow star cookie being held up — We have used this simple sugar cookie icing on hundreds of cookies spanning many decades. It’s easy, great for spreading or piping, and hardens glossy with a stackable finish.

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Best Sugar Cookie Icing That Hardens

The trick for how to make hard icing glaze is in the ingredients. A mixture of powdered sugar, milk, and light corn syrup blends together to make smooth, perfect sugar cookie icing.

The small amount of corn syrup achieves a shiny, glossy surface, and thickens the frosting to make for easier decorating. When it dries with the milk and powdered sugar, you are left with hard frosting. The trick is to leave the cookies set for at least 12 hours for the frosting to set up.

Unlike a fluffy buttercream frosting, there is no butter or fat in the recipe, so it hardens similarly to royal frosting. But unlike royal icing, which uses egg whites or meringue powder, the ingredients are right in your pantry.

This recipe is so easy and really does dry quickly and shiny. I have avoided icing cookies for years because of the time and trouble but with this recipe it’s so easy! For the holidays I used peppermint extract. Did this with the ladies at church and they loved it! We just used small spatulas (honey, cheese spreaders, etc.) instead of trying to pipe it and it worked great!
—Wendy

Why is this THE Sugar Cookie Icing?

Christmas would not be complete without my mom’s tried-and-true rolled sugar cookies making an appearance. This cookie icing was an integral part of our holidays, and deemed the best over the years.

While Mom rolled, cut, and baked the cookies, we were tasked with covering the kitchen with frosting and sprinkles. Sometimes some of it even landed on the cookies.

These homemade with love creations were often gifted to teachers and neighbors, and since the icing hardens into a beautiful glassy surface it’s durable enough to be wrapped and transported. It’s like a sugar force field for cookies.

(Now that I’m pondering it…that’s most likely why Mom sent us with her famous homemade peanut brittle and paper bag microwave caramel corn for teacher’s gifts. They’re also delicious and durable!)

I now enjoy this same tradition with my own kids, but instead use this recipe for gluten-free sugar cookies that tastes just like the old-fashioned ones Mom made!

Let’s Make This Together!

(Below shows step-by-step photos and modified instructions. For the complete recipe, along with ingredient amounts, scroll down to the recipe card.)

Just mix – it’s that simple

Add the powdered sugar to a bowl. If you don’t want lumps, you can sift it first, but honestly I never do this. I just stir a little more vigorously. Add the milk, holding back a bit, corn syrup, and almond extract.

Stir until no lumps remain and icing is smooth and glossy. You’ll want it to thickly fall off the spoon. If it’s too thick, stir in the remaining milk.

If making different colors of icing, divide into separate bowls and add food coloring. Gel coloring will be more vibrant, liquid dye more muted. There’s nothing wrong with pink Santas, though!

a spoon lifting out sugar cooking icing from a glass bowl

Time to decorate…with options

If I’m making this with kids, we just take small spreaders and smooth it on the cookies. We might even pull out some toothpicks for “detail” work, but that’s about as complicated as we get.

Looking for a more profesh, leveled-up cookie decorating? Then I suggest transferring the icing into piping bags with tips. I fold the bag over a tall glass cup and then scoop the frosting in.

Use a round decorating tip to outline the cookie with icing. With that same tip, fill in the outline until it’s all covered and absolutely lovely looking. A small knife or toothpick helps smooth over any gaps.

If using sprinkles, for either method, decorate immediately. The top layer will harden quickly. Be real proud of yourself – those are some good looking cookies!

the icing going into a decorative piping bag.

a green frosting outline on a heart shaped cookie.

How Long Does it Take To Harden?

It will take 12-24 hours for the icing to harden, depending on the thickness of the frosting. For best results, set decorated cookies on a baking sheet in a single layer and leave overnight.

Before stacking, wrapping, or storing make sure the icing is hard throughout. The top layer will feel hard to the touch first before it dries throughout. Then they may be stacked and stored. Enjoying the cookies can happen at any time – doesn’t need to be hard for that!

Can I Make This Without Corn Syrup?

Yes…and no. The recipe may be adjusted to omit the corn syrup and add 1-2 teaspoons additional milk for the right spreadable consistency.

However, corn syrup is what achieves that glossy finish. It also prevents the icing from being runny, which makes decorating and spreading the frosting on the cookies easier.

a child's hand picking up a decorated sugar cookie — We like to make one big batch and divide it up in cups for different colors. Gel food colors are more vibrant while liquid food coloring is great for pastels.

Wondering what kind of food coloring to use? Gel food coloring is highly pigmented so you can achieve very bright colors. This works best with powdered sugar icing since it is bright white. Otherwise, a lot of food coloring would have to be added to offset the white. Liquid food dye works best for pastel colors because you don’t need to add as much to the frosting. It is also readily available at any grocery store.

a platter of decorated cookies — Grab your favorite sugar cookie recipe, frost, and let the sprinkles fly! We lay our cookies flat on a baking sheet for several hours before stacking to store.

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Did you make this recipe? I love hearing from you! Leave a star rating and comment below the recipe card. It helps others when searching for recipes and I appreciate feedback from our community. You will always hear back from me! -Melissa

4.06 stars (253 ratings)