Line cookie sheet with aluminum foil and sprinkle liberally with powdered sugar. In heavy 2-quart saucepan, combine sugar, water and corn syrup over medium heat until sugar dissolves. Boil to 310 F without stirring. Hard crack will occur when mixture is drizzled into cold water. Remove from heat and stir in flavoring and food coloring. Pour mixture onto prepared cookie sheet and allow to cool completely. Break into pieces.