For the blackberry crumble, first grease an ovenproof dish. Preheat the oven to 180 °C. Sort the blackberries. Wash, core and chop the apples.
Mix the fruit with the sugar and put it into the baking dish.
For the crumble, knead all the ingredients until they become coarse crumbs. Sprinkle over the fruit and bake the blackberry crumble for about 45 minutes.