Remove the stem of the apples and wash and dry the apples thoroughly. I fully submerged the apples in really hot water for 10 minutes to remove the wave from the apples.
Stick a candy apple stick or lollipop stick in the top of the apple where the stem was and place on a piece of parchment paper located close to where you're making the sugar mixture.
In a large saucepan, add in the granulated sugar, water, and corn syrup.
Place over medium heat and stir until everything is combined. Let it boil and come up to 300 degrees F. I would highly recommend using a candy thermometer for this.
Remove the candy from the heat and stir in the red food color and cinnamon oil if you're using it. Cinnamon oil tends to be really strong so be very cautious when adding drops.
Quickly begin dipping the apples in the hot candy. Carefully tilt the pot on its side slightly and roll the apple in the mixture. Let it drip off for a few seconds and set on the parchment paper.
Let cool completely until the candy apples are fully hardened and then you can move them.