Preheat the oven to 350°F (180°C). Lightly grease a baking dish.
Spread the cherry pie filling evenly in the baking dish.
Add the drained crushed pineapple over the cherry pie filling, layering it evenly.
Sprinkle the dry yellow cake mix over the top.
Drizzle melted butter across the surface, covering as much of the cake mix as possible.
Bake in the oven for about 40–45 minutes until the top is golden and the edges are bubbling.
Serve warm, preferably with a scoop of vanilla ice cream.
