Prepare Apples - Remove the stems of the apples and thoroughly wash them. Place the clean apples on a sheet pan sprayed with cooking spray to allow them to dry.
Prepare the Sugar Mixture - In a medium saucepan, combine the sugar, corn syrup, white food coloring, and pink gel food coloring using a wooden spoon. Cook the mixture on medium heat until it boils.
Use a Candy Thermometer to Monitor the Mix - When the mixture begins to boil, stick a candy thermometer on the side of the pan. Be sure that the thermometer is well in the mixture, but not touching the bottom.
The mixture should reach 302 degrees Fahrenheit. This may take up to 20 minutes, but the mixture does not need to be stirred in the process.
Remove from Heat - Once the mixture has reached 302 degrees Fahrenheit, remove it from the heat. Use a rubber spatula to stir in the vanilla extract, making sure it is fully incorporated.
Dip the Apples - Carefully dip the apples into the sugar mixture. Swirl them around to make sure they are fully coated, allow the excess sugar mixture to drip off. Place the apples on the sheet pan to allow them to fully dry.
Be certain to be careful when dipping the apples, as the sugar mixture will be hot. It is best to tilt the pan to make it easier to dip.