Directions

• Prep Work
• Dice your unsalted butter into small cubes and keep it chilling in the refrigerator until the exact moment you use it.
• Lightly spray a 15cm square baking pan with oil and line it smoothly with parchment paper.
• Preheat your oven to 180°C (350°F).
• Making the Crumble Mixture
• Add all of your crumble ingredients, the cake flour, almond flour, granulated sugar, salt, and the ice-cold cubed butter, directly into the bowl of a food processor. Pulse the mixture in short bursts for just a few seconds until the butter breaks down and the mixture looks completely sandy, fine, and uniform. (Tip: If you don’t have a food processor, add the ingredients to a large bowl and quickly rub the cold butter into the dry ingredients using your fingertips until a sandy texture is achieved).
• Creating the Small Clusters
• Transfer the sandy flour mixture into a clean plastic bag (like a ziplock or food storage bag). Use your hands to gently press and squeeze the dough inside the bag a few times to encourage the fine sand to clump up into small, rustic pebbled clusters.
• Pressing the Bottom Crust
• Weigh out exactly 230g of your prepared crumble mixture and pour it into the bottom of your lined square pan. Use the flat bottom of a rolling pin, a glass, or a measuring cup to firmly and evenly press the mixture down into a solid, flat crust. Place this pan, along with the remaining loose crumble mixture, into the freezer to rest while you prepare the fruit.
• The Bright Berry Filling
• Measure your blueberries and raspberries into a medium mixing bowl. If your raspberries are quite large, gently break them apart into smaller pieces with your fingers. Sprinkle the 30g of granulated sugar and 7g of cornstarch over the fruit and toss everything together thoroughly until the berries are completely and evenly coated.
• Assemble the Layers
• Retrieve your chilled crust from the freezer. Spread the sugar-coated berry mixture evenly across the firm crumble base, smoothing it right to the edges. Take the remaining loose crumble mixture and scatter it generously over the top of the berries, covering them beautifully.
• Bake to a Golden Brown
• Bake in your preheated oven at 180°C (350°F).
• If using fresh blueberries: Bake for about 40 minutes.
• If using frozen blueberries: Bake for 50 to 60 minutes. You want the berry juices to bubble lazily along the edges and the crumble topping to turn a gorgeous, light golden-brown color.
• Chill and Slice
• Remove the pan from the oven and let it cool completely to room temperature on a wire rack. Once cool, place the entire pan into the refrigerator and let it chill thoroughly for at least an hour. Once cold, lift the parchment paper out of the pan and use a sharp chef’s knife to cleanly slice the square into 9 uniform bars.