Ingredients:

  • 1 1/2 cups All-purpose flour
  • 1/2 cup Rolled oats
  • 1/2 cup packed Light brown sugar
  • 1/4 cup Granulated sugar (for topping)
  • 1 tsp Ground cinnamon
  • 6 oz Unsalted butter, cubed and chilled
  • 4 cups Fresh or frozen blueberries
  • 1/4 cup Granulated sugar (for filling)
  • 2 Tbsp Cornstarch (Cornflour)
  • 1 tsp Lemon Zest
  • 1/8 tsp Salt

Instructions:

  1. Preheat the oven to 375°F (190°C). Lightly grease a 9-inch baking dish.
  2. Construct the Crumble Topping: In a large mixing bowl, whisk together the flour, rolled oats, both sugars, and cinnamon. Scatter the cold, cubed butter over the dry ingredients. Using your fingertips, quickly rub the butter into the flour mixture until the mixture resembles coarse breadcrumbs. Set aside.
  3. Prepare the Blueberry Filling: In a separate medium bowl, combine the blueberries (no need to thaw if frozen), granulated sugar, cornstarch, lemon zest, and salt. Toss gently until the cornstarch is evenly distributed and the berries are lightly coated.
  4. Assemble and Bake: Pour the berry mixture evenly into the prepared baking dish. Sprinkle the crumble topping evenly over the blueberries, ensuring the filling is fully covered. Do not press the topping down.
  5. Bake for 40 to 45 minutes, or until the topping is deeply golden brown and the blueberry filling is visibly bubbling thickly around the edges.
  6. Cool and Serve: Remove the crumble from the oven and let it rest on a wire rack for at least 15 minutes. This resting time allows the fruit juices to cool and set properly. Serve warm with custard or ice cream.