Heat the oven to 350 F.
In a large cast iron skillet, heat the butter over medium-high heat.
Add the sliced apples, brown sugar, cinnamon and nutmeg, and cook until the apples are slightly softened, about 8-10 minutes.
Add the caramel dip and salt, and stir well to combine. Remove from heat.
In a medium-sized bowl, combine the flour, oats, brown sugar, cinnamon, salt and melted butter. Stir well.
Sprinkle the oat topping over the apple filling. Note: you can bake the apple crisp directly in the cast iron skillet or transfer it to a 9×9 baking dish.
Bake for 40-45 minutes until golden brown and bubbling.
Serve with vanilla ice cream and additional caramel dip.