Royal icing is our go-to for decorating cookies. It's easy to work with and sets up firmly when dry. It is commonly used for decorating gingerbread cookies and for piping decorations.
How to Make Royal Icing:
Test Kitchen Tip: Meringue powder can be found in the cake decorating aisle of hobby and crafts stores.
Makes about 2-1/2 cups icing.
Piping Royal icing starts out thick -- perfect for piping outlines and accents. Pipe the outline, then let it dry before filling in the cookie.
Flooding To thin the icing for filling in large areas, stir in additional warm water, about 1/2 teaspoon at a time, until the icing is a thick, spoonable glaze. Fill in outlined cookies with the spreadable royal icing.
Food coloring can be found in different forms -- paste coloring, gel coloring, and classic liquid coloring.
Paste: There's a lovely range of colors available, but you'll have to visit a hobby store to find this type of food coloring. The paste can be thick and hard to blend into frosting.
Gel: The smooth consistency of gel coloring makes it easy to stir into frosting. This can be found online and in some hobby stores.
Liquid food coloring: Available at most grocery stores, liquid food coloring usually comes in four color options: red, yellow, green, and blue. It takes some experimenting, but the colors can be mixed to create new colors.