For a quick and easy way to finish petits fours, use our colorful royal icing decorating kit. Mix the icing to a glaze consistency according to the package instructions. Space the cooled petits fours a few inches apart on a wire rack set over parchment paper or a baking sheet, then decorate as desired:
-Spoon the colored glaze over the tops of the little cakes, allowing some to drip down the sides. If desired, pour on the glaze so it completely covers the cakes (this is best done over a baking sheet). Let the glaze set for at least 30 minutes.
-For additional decoration, pipe a different color of glaze on top of the cakes, or sprinkle the cakes with the dusting sugars.
-Instead of royal icing, drizzle or pour white chocolate ganache over the petits fours.
-For an easy decoration, simply sift the dusting sugars over the plain cakes.
Williams-Sonoma Test Kitchen