Preheat oven to 350 degrees Fahrenheit.

In a food processor, pulse crackers, pretzels, cereal, and sugar until the mixture has the texture of chunky crumbs.

Transfer to a bowl and mix in the caramel sauce.

Transfer to the crust and top with caramel chips.

Bake five minutes, remove from the oven, and spread caramel into a smooth layer.

Freeze until the pie sets, about one hour. Let sit at room temperature 30 minutes before serving.