Sugar Cookies with Royal Icing - Uwajimaya

Ingredients

• ¾ cup softened butter (1 ½ sticks)
• ¾ cup sugar
• 1 large egg
• 1 teaspoon vanilla extract
• 1 tablespoon grated orange peel
• 2 ¼ cups all-purpose flour
• ¼ teaspoon salt
• 3 large egg whites
• 1 pound confectioners’ sugar (1 box)
• Food coloring