Cover countertop or work surface with a silicone baking mat.

In a large, heavy-bottomed stock pot, stir together granulated sugar, corn syrup, and water. Cook over medium heat, stirring occasionally until the sugar dissolves.

Once sugar dissolves, stop stirring and add a candy thermometer to monitor the temperature (or keep a hand-held digital thermometer nearby!) Cook the sugar mixture until it reaches 300° F / 149° C on a candy thermometer, periodically swirling the pan as needed, and brushing down the sides with a wet pastry brush to prevent crystallization. (Cooking the sugar will take about 15-20 minutes, so be patient!)

Remove from heat. Stir in flavoring and gel food coloring.

Immediately pour hot sugar mixture onto prepared baking mat, and allow to cool completely. (This will happen very quickly, about 15-20 minutes.)

Once cool, use your hands or a kitchen mallet to break the slab into small pieces. Toss in confectioner’s sugar to coat.

Store old-fashioned hard candy in an airtight container at room temperature for up to three months.