Preheat oven to 180°C (both fan and standard).
Apple - Peel apples, then cut into cubes.
Fruit filling - Place fruit in a bowl. Sprinkle with cornflour, sugar and cinnamon, then pour over lemon juice. Toss, then spread out evenly in a baking dish. No need to defrost if frozen.
Crumble topping - Place Topping ingredients in a bowl. Mix until clumps form. Spread over the fruit, crumbling with fingers if required to get that crumbly topping.
Bake for 30 to 40 minutes or until golden brown. Remove, cover loosely with foil to keep warm and let stand for 10 minutes before serving (lets the syrup thicken slightly).
Serve warm with vanilla ice cream!
