This royal Icing recipe is great for decorating sugar cookies. It dries smooth and has a hard matte finish and is great for cookie and cake decorations.
Sugar Cookie Decorating 101
Apparently, the best icing for sugar cookies. It hardens nicely so you can stack cookies, but doesn't get hard like a rock so you won't hurt your teeth. It's very tasty too and you can add different extracts to change the flavors.