Spray a 9x13 baking dish with nonstick cooking spray.
Evenly spread the cherry pie filling from both cans into the prepared baking dish.
Scatter the dry cake mix evenly over the cherries.
Place the butter slices uniformly over the cake mix layer.
Bake for about 50-60 minutes, until the cake mix is golden brown on top. Allow it to cool for at least 10 minutes before serving. Enjoy it warm or at room temperature, perhaps with a scoop of vanilla ice cream.