Preheat the oven to 180°C (350℉).
Rinse your berries, prepare by removing stalks/stones and slice them up. Place them in a large pie dish or ceramic oven dish.
300 g strawberries, 100 g cherries, 50 g blueberries
Sprinkle the fruit with the granulated sugar.
20 g granulated sugar
In another bowl, measure out the plain flour, then cube the cold butter and add it in with the flour.
160 g plain flour (all-purpose flour), 100 g unsalted butter
Using your fingertips, lightly rub the butter into the flour until it has the texture of medium-fine breadcrumbs.
Stir in the demerara sugar.
90 g demerara sugar
Sprinkle your crumble topping over the fruit in your dish, as evenly as you can.
Bake for 30-35 minutes until the top of the crumble is golden and the juices start to ooze out of the fruit around the sides of the dish,