Prepare a large, sided baking sheet by spraying with nonstick cooking spray. Use a paper towel to rub the spray around on the pan to ensure even coverage and prevent pooling of the spray.

Add the ingredients to a large pot with a candy thermometer on the side. Heat over medium, stirring occasionally to help the sugar dissolve.

Bring the mixture to a boil until it reaches 300 degrees F. If you are not using a candy thermometer, at this point the candy will harden into threads when dropped into cold water. The candy needs to get to temperature to properly harden.

Once the mixture reaches 300 degrees F, remove it from heat and stir in food coloring and flavor extract (if using). Pour the liquid sugar into the prepared baking sheet. Allow it to cool at room temperature or in the refrigerator. Once set, it will be rock hard and can be broken into pieces.