Prepare Your Tin and Oven: Preheat your oven to 180°C (160°C fan). Grease and line the base of a 23cm (9-inch) springform tin with baking parchment.

Make the Biscuit Base: Crush the digestive biscuits into fine crumbs using a food processor or by placing them in a bag and bashing with a rolling pin. Mix the crumbs with the melted butter until well combined. Press the mixture firmly and evenly into the base of the prepared tin. Bake for 10 minutes, then set aside to cool completely. Reduce the oven temperature to 160°C (140°C fan).

Create the Blueberry Compote: While the base cools, place the blueberries, sugar, and lemon juice in a small saucepan over medium heat. Cook for 5-7 minutes, stirring occasionally, until the berries start to burst and release their juices. Stir in the cornflour slurry and cook for another minute until the sauce thickens. Remove from the heat and let it cool.

Mix the Crumble Topping: In a separate bowl, combine the plain flour, rolled oats, and demerara sugar. Add the cold, cubed butter. Using your fingertips, rub the butter into the dry ingredients until the mixture resembles coarse breadcrumbs. Set aside.

Make the Cheesecake Filling: In a large bowl using a stand mixer with the paddle attachment or a hand mixer, beat the room temperature cream cheese on a low speed until smooth. I find that keeping the speed low is crucial to avoid whipping in too much air. Gradually beat in the caster sugar, followed by the vanilla extract. Add the eggs one at a time, mixing gently after each addition until just combined. Finally, fold in the soured cream. Be careful not to over-mix.

Assemble the Cheesecake: Pour the cheesecake filling over the cooled biscuit base. Spoon about half of the cooled blueberry compote in dollops over the top. Use a skewer or knife to gently swirl the compote through the filling to create a marbled effect.

Add Topping and Bake: Sprinkle the crumble mixture evenly over the top of the cheesecake. Place the tin on a baking tray and bake for 60-70 minutes. The cheesecake is ready when the edges are set and pale golden, but the centre still has a distinct wobble.

Cool Down Slowly: This is the most important step for a crack-free cheesecake! Turn off the oven and leave the door ajar with the cheesecake still inside for 1 hour. Then, remove it from the oven and let it cool completely at room temperature. Once cool, cover and refrigerate for at least 6 hours, or preferably overnight, to set fully.

Serve: Once chilled and firm, carefully run a knife around the edge of the cheesecake before releasing the springform tin. Serve chilled, with the remaining blueberry compote spooned over the top of each slice.