Melt the butter in a saucepan over a medium heat. Add the brown sugar and cook until melted and combined.
Add the cinnamon, prunes and apples and cook until the apples become very soft.
Transfer the fruit mixture to a shallow ovenproof dish.
For the crumble, place all of the crumble ingredients together into a food processor and blend until combined. Sprinkle the crumble mixture on top of the fruit and transfer to the oven to bake for 10-15 minutes, or until the crumble topping is crisp and golden-brown.
For the brandy cream, add the brandy to the whipped cream in a bowl and fold together.
Serve the crumble in the cooking dish with the brandy cream in a serving bowl alongside.