Plum and Hazelnut Crumble

|The humble crumble is a beautiful way to show off summer fruit. This is an excellent way to use up an abundance of ripe plums.|plums|For the oat and hazelnut crumble:150g plain flour150g soft dark brown sugara pinch of table salt1 teaspoon ground cinnamon150g unsalted butter diced150g jumbo or porridge oats80g hazelnuts choppedFor the plum filling:800g plums (use one type or a selection such as bullaces damsons mirabelles greengages) stones removed then plums left whole if small otherwise cut in half200g soft dark brown sugar1 teaspoon ground cinnamon100g ground almonds100g fresh breadcrumbs|First prepare the oat and hazelnut crumble. Preheat the oven to 180°C/Gas Mark 4 and line a baking tray with non-stick baking paper. Place the flour brown sugar salt cinnamon and butter in a mixing bowl then use your fingertips to rub the butter into the flour mixture until the mixture resembles coarse breadcrumbs. Stir in the oats and chopped hazelnuts then transfer the crumble mixture to the prepared baking tray and spread it out evenly. Bake in the oven for about 20 minutes or until light golden and semi-crisp stirring it once during cooking.Remove from the oven and leave the mixture to cool on the baking tray for about 1 hour. Bits of the crumble will have stuck together almost like flapjacks so break these up into crumb-size pieces using your fingers. Once cold the crumble mixture can be transferred to an airtight container and kept in the fridge for up to 1 week (it will lose a little of its crispness during storage but once it is baked for the second time it will crisp up again and be perfect).For the plum filling preheat the oven to 180°C/Gas Mark 4. Place all the ingredients for the filling in a large mixing bowl and mix them together using your hands. Select your ovenproof serving dish (use either one large oven-to-table dish or 6 individual dishes). Spoon the fruit mixture into the dish and then bake in the oven for 15 minutes or until the mixture has thickened and the fruit has collapsed.Remove from the oven. Cover the fruit mixture with the crumble mixture crumbs then return to the oven and bake for a further 10-12 minutes or until the crumble topping has crisped up and turned golden brown. Serve will still warm or allow to cool. Goes well topped with vanilla custard.|35.00 minutes|6|British Larder