Preheat the oven to 350°F and grease a 9x13-inch pan with cooking spray.
Dump the pie filling into the baking sheet and spread out to the edges.
Sprinkle the dry cake mix over the top of the strawberry filling as evenly as possible.
Slice the butter into thin slices and place evenly over the top of the cake mix.
Sprinkle the top with cinnamon sugar and bake for 40 to 45 minutes until the cake is golden brown.
Serve warm or room temperature with ice cream and whipped cream.
