Cook and stir over medium heat until sugar dissolves. Wash down sugar crystals on sides of pan with wet brush. Blend in confectioners sugar gradually, beating until smooth. Add flavoring and food colors. Thin down frosting with a few tsp hot water until pouring consistency.
Place petits fours on wire rack over wax paper.
Slowly pour frosting by tsp over cake. Spreading evenly with a small spatula. Scrape up drippings and re-use, adding a little water.