McCormick and Taste of Home both offer recipes for orange-flavored icing. The recipe from McCormick relies on orange extract, while Taste of Home's recipe uses orange juice and fresh orange peel for flavor.
To make McCormick's orange-flavored icing, beat 2 sticks of softened butter with an electric mixer until light and fluffy. Pour in 1 teaspoon of orange extract, and continue to mix until blended.
Add 1 16-ounce package of confectioners' sugar gradually. Beat with the electric mixer each time sugar is added to ensure the sugar is fully incorporated. Scrape the bottom and sides of the mixing bowl as needed.
Add 2 tablespoons of milk, and continue to mix. If desired, add food coloring. McCormick recommends using 12 drops of yellow food coloring and 4 drops of red food coloring to achieve an orange color. Beat until the milk and food coloring are completely incorporated and the icing is light and fluffy.
To make Taste of Home's orange-flavored icing, cream 1/4 cup of butter with 2 cups of confectioners' sugar. Add 1 teaspoon of grated orange peel and 3/4 teaspoon of vanilla extract, and continue to mix.
Gradually add to 2 to 3 tablespoons of orange juice to the icing, stopping when the desired consistency is reached. Continue mixing the icing while adding the orange juice.