Wash all fresh fruits thoroughly before using. Set aside to dry.
Preheat oven to 375 degrees. Lightly spray a 9” x9” baking dish with cooking spray.
In a large bowl, combine blackberries, splenda, flour, vanilla extract and cinnamon. Place in baking dish.
In a small bowl, combine old fashioned oats, splenda, flour and cinnamon. With a knife, cut into the dry mixture the butter until crumbly in appearance. Sprinkle topping mixture evenly over fruit in baking dish.
Place in preheated oven and bake for 45 minutes or until blackberries are done.
Portion ½ c servings into serving dish. Use immediately or refrigerate for up to 3 days.