Preheat the oven to 350°F. Melt 2 Tbsp of butter, cube the rest. Swirl the melted butter to coat the bottom and sides of a 10-inch cast iron skillet or similar.
Arrange the apple slices evenly in the skillet overlapping.
Drizzle the apples with the apple cider.
In a small bowl, mix together the brown sugar, ground cinnamon and nutmeg.
Sprinkle over the apples. Arrange the pecan pieces and cubed butter on top.
Bake for 45-50 minutes or until tender.
Warm the dulce de leche in a microwave safe bowl and drizzle on top.
Serve warm with vanilla ice cream.