Step 1

Preheat the oven to 350 degrees F (175 degrees C). Lightly grease a 9x13-inch baking pan with cooking spray.

Step 2

Spread apple pie filling in an even layer on the bottom of the pan. Drizzle caramel sauce evenly over apples. Sprinkle cake mix evenly over apples and caramel. Drizzle melted butter evenly over cake mix. Sprinkle evenly with chopped walnuts.

Step 3

Bake in the preheated oven until cake is golden brown and the filling is bubbling through to the top, 50 to 55 minutes. Let cool at least 15 minutes. Serve warm or at room temperature.