Preheat the oven to 350 degrees.
Lightly spray a 9x13 baking dish with cooking spray.
Spread the berries in an even layer over bottom of the pan.
Add the dry cake mix over the top.
Slowly pour soda over the top of the cake mix, making sure you moisten nearly all of the dry mix which will give you your crust.
DO NOT STIR - if you stir you will have a top more like cake- not crust.
Bake 45-60 minutes watching closely after the 45 min mark - allow it to brown on top.
If you want it really brown you can broil the top for a couple minutes.
Remove & allow to cool slightly before serving.
We prefer ours with a scoop of vanilla ice cream or whipped cream on top