Preheat oven to 425 degrees F.
Peel 6 apples and slice a small portion off of the bottoms so that they sit well without tumbling over. Place in a greased iron skillet or other heavy-bottomed skillet.
Peel remaining two apples, core and dice into a medium dice. Combine softened butter, chopped apple, ½ cup brown sugar, oats, Heath bits ‘o brickle, pecans, cinnamon and salt. Mix well to combine.
Stuff each apple with stuffing, filling the cavity and mounding it generously on top, pressing with the palm of a cupped hand to secure filling.
Pour ½ cup bourbon or apple juice, and 4 tablespoons butter around apples.
Place stuffed apples in preheated oven and bake for about 20 minutes or until apples are fork-tender. Remove from oven and carefully remove apples with a spatula to a serving platter.
For Sauce:
Heat remaining juices (adding more bourbon or apple juice if needed), and bring to a boil over medium-high heat. Add brown sugar and stir with a wooden spoon and reduce liquid until it reaches a syrup-consistency sauce (thick enough to coat the back of a spoon).
Serve warm with sauce and ice cream, if desired.