Drain the pineapple tidbits of their juice. Combine in a large bowl with cherry filling and extract. Use a rubber spatula to mix.
Pour the contents into a 2 quart baking dish. Dust the dried yellow cake mix over the casserole dish, covering all of the fruit filling.
Pour melted butter over the dry cake mix. Use a spoon to spread it evenly as best as possible, covering all of the dried mix.
Bake at a 350F oven for 45 minutes. Top will be golden brown.
When baked as directed, this dessert comes out much like a cobbler. The topping is much more crunchy and biscuit-like. If you would rather more of a cake-like topping, you would make this in a 9x13 casserole dish, and make the cake mix into a batter based on package instructions. Pour the batter on top of the fruit filling and bake.
To make this a bit more like a pineapple upside down dump cake, use rum extract in place of the vanilla extract.