Preheat oven to 350° F (325°F for glass baking dish). Grease a 9×13 baking pan.
Dump apple pie filling into the baking dish and spread it out evenly.
Sprinkle the cake mix evenly over the apple pie filling.
Cut butter into slices with a butter knife and place slices evenly over cake mix.
Bake for one hour.
To serve, scoop cake out with a large spoon like a cobbler, and dump it on a nice plate. A scoop of vanilla ice cream dumped on top is delicious! Serve warm or cold.