Add fries to a heat-safe skillet. Heat the fries until golden and crisp, about 30 minutes. Move the fries around a bit while baking so they all get access to the heat.
Carefully remove the skillet from the oven, and sprinkle most of the pepperoni on top of the baked fries. Pour pizza sauce evenly on top. Sprinkle cheese on next, and then some more pepperoni.
Return the skillet to the oven for an additional 5 minutes or so- until the cheese has melted.