McIntosh apples seem to be the classic apple to use for caramel apples but try Pink Ladies, Granny Smith or use your favourite apple.
Line a baking sheet with parchment paper. Make sure to wash and completely dry the apples, give them a polish too – this will ensure the caramel sticks to the apple. Firmly insert stick into stem end of each apple. Set aside.
Add sugar, butter, cream, corn syrup and salt to a tall saucepan (the pan needs to be tall enough so the apple can be immersed in the caramel but smaller in width so you get the right volume to dip.) Over medium-low heat, stir the mixture until the butter is melted.
Bring mixture to a boil over medium-high heat, stirring frequently, until the temperature reads 245 degrees F, about 9 minutes. The mixture will thicken. When the caramel has reached 245 degrees F. remove immediately from the heat and place the bottom of the pot in a stainless steel bowl (or larger pot) of ice water to stop the caramel from cooking further. Be careful not to get any water in the caramel. Remove caramel from the ice bath. Stir the vanilla into the caramel. Let caramel cool slightly to 200 degree F., about 5 minutes, before dipping.
Dip the apple into the caramel, holding the apple firmly by the popsicle stick. Be careful not to touch the caramel, it’s extremely hot. Slowly lift the apple out of the caramel letting the excess drip off back into the pot of caramel. Twirling the apple gently will help to remove excess caramel. Place apple on prepared baking sheet.
Note if all the caramel runs off the apple, let caramel cool a couple of minutes more. If caramel becomes too thick to work with, gently warm it over low heat for a few seconds.
Let caramel cool completely on apples before eating, approximately 30 minutes.