Grease a 12 inch round pan with nonstick baking spray.
In a large saucepan, add in the granulated sugar, corn syrup, and water. Place over medium heat, stir until combined and let it cook to 300 degrees F. I would highly recommend using a candy thermometer for this.
After the sugar mixture has reached 300 degrees F, remove from the heat. Quickly add in a few drops of gel food coloring and the cinnamon oil. Stir vigorously until combined.
Quickly pour the hot sugar mixture onto the prepared pan. Let it cool for 20-30 minutes.
Tap on the round pan to release the sheet of candy. Dust both sides of the candy with powdered sugar. Bust the sheet of candy into small pieces and place into an airtight container.
Cinnamon Rock Candy https://www.cookiedoughandovenmitt.com/cinnamon-rock-candy/