Preheat oven to 350*. In a mixing bowl, combine dry cake mix, rolled oats and melted butter. Stir to combine well, ensuring mix is fully incorporated with the oats. It will be crumbly.

Grease or spray a 9X13 pan. Press half of the cake mixture firmly into the bottom of the pan.  In a separate bowl, combine raspberry preserves with water. Spread evenly on the bottom cake layer, allowing 1” from all sides of the pan.

Crumble remaining cake mixture on top of raspberry layer and gently press into place.

Bake at 350* for 17-20 minutes, or until the crumble top is nicely golden brown. Remove from oven and let cool before serving so the preserves set up a bit.