Directions to make the Apple and Blackberry Crumble
Preheat oven to 180 C / Gas 4.
For the fruit base: Place apples and blackberries in a 20x30cm or similar sized baking dish. Mix together caster sugar, flour and cinnamon together. Sprinkle over fruit. Pour water all over.
For the crumble topping: Combine oats, walnuts, flour, sugar, baking powder, bicarbonate of soda and melted butter. Crumble evenly over the fruit.
Bake crumble in preheated oven for about 45 minutes.