Place apples on a cutting board. With a sharp knife, carefully cut the top 1/2 inch from the top of each.
Using an apple corer or a small melon baller, scoop out the stem, core and seeds from each apple, leaving the bottom intact. Stand the apples in a 9 inch square baking dish, cut side up.
Divide 1/4 cup each chopped Snickers and Skor/Heath bar candy bars among the apples, about 2 tablespoons of candy per apple.
Place 1 1/2 teaspoon of butter inside each apple, on top of the candy bar pieces. Then divide the remainder 1/4 cup chopped candy bars among the apples.
In a small bowl, whisk together the cider and sugar and pour mixture over and around the apples. Carefully place baking dish in the oven and bake the apples uncovered until tender, about 1 hour and 20 minutes. (Original recipes states 1 hour and 20 minutes, but if cooked too long the apples become mealy. Start checking around 45 minutes.) Remove from oven and let sit 5 minutes.
Serve hot or warm, spoon the pan juices over apples and add vanilla ice cream if desired.