Preheat the camp oven (closed grill or smoker) to a temperature of 300 degrees F (150 degrees C).
Gently melt the chocolate and milk while stirring until all melted and well combined. Do not let boil.
Place the pre-made pie crust in the skillet then pour in the melted chocolate.Tip: By placing the pie in a skillet it will make it easier to handle and protect the base/filling as the cast iron heats up, this also maximizes the heat to the marshmallow and getting a perfect brown crust.
Evenly spread the marshmallows over the top of the chocolate filling.
Place the skillet, with the smores pie in it, into the preheated camp oven. Cook until the marshmallows are golden brown.