Cookie Crust

Before you begin, heat the oven to 160ºC / 325ºF conventional. Line the base of a 23 cm / 9-inch springform tin with parchment paper.

Place the cookies and granulated sugar in a food processor and pulse until you get a fine, sand-like crumb. Melt the butter, add it to the processor, and blend again until the crumbs fully absorb the butter.

Transfer the mixture into the springform pan. Use the base of a glass to press the crumbs firmly across the bottom and a little way up the sides of the pan. Pack the crust tightly so it holds together after baking.

Bake the crust for 10 minutes. Remove it from the oven and let it cool until it no longer feels warm to the touch. Leave the oven on.

Blueberries and Crumble

While the crust bakes, prepare the topping components.

For the blueberries, add the blueberries, granulated sugar, and flour to a small bowl. Stir to coat the berries evenly. Add the lemon juice and mix again until the flour disappears and the berries look glossy and coated. Set this mixture aside.

For the crumble, combine the flour and dark brown sugar in a separate bowl. Pour the melted butter over the mixture. Use a fork to toss everything together until it forms a rough, crumbly texture and no dry flour remains. Set the blueberry mixture and the crumble aside while you make the filling.

Cheesecake

Using a hand mixer or a stand mixer fitted with the paddle attachment, beat the cream cheese on low speed for about 1 minute so it softens and becomes smooth. Add the granulated sugar and continue mixing on low speed for another minute. Scrape down the sides of the bowl and mix again for about 30 seconds so the sugar blends evenly.

In a small bowl, stir the sour cream and cornstarch together until the mixture turns smooth. Add that mixture to the cream cheese along with the vanilla extract. Mix on low speed until everything comes together.

Add the eggs two at a time, mixing on low speed after each addition. Once all the eggs have been incorporated, scrape down the bowl again and give the batter one final gentle mix so no streaks remain.

Pour the cheesecake batter into the cooled crust. Spoon the blueberries over the top in an even layer, then scatter the crumble across the surface.

Boil water in a kettle. Place the springform pan inside a 30 cm / 12-inch cake pan. Put that cake pan inside a second baking pan or roasting pan and pour the hot water into the outer pan. This creates the water bath while keeping the crust protected from direct contact with the water.

As another option, wrap the outside of the springform pan with three layers of aluminum foil before setting it in the water bath. Seal it carefully, because any gaps can let water seep in. If you use this method, check the wrapping closely before baking.

Bake the cheesecake for 1 hour and 20 to 30 minutes.

When the baking time is complete, gently shake the tray. The center should still quiver slightly. That small wobble means the Blueberry Crumble Cheesecake is done enough to continue setting as it cools.

Switch the oven off, crack the oven door open slightly, and let the cheesecake sit inside for 1 hour. This slow cooling step helps the texture stay smooth and reduces the risk of cracking.

After the hour has passed, remove the cheesecake from the oven and lift it out of the water bath. Place it on a cooling rack and allow it to cool fully at room temperature for about 1 hour.

Once it has reached room temperature, move the Blueberry Crumble Cheesecake to the refrigerator. Chill it for at least 6 hours, though overnight chilling gives the best slice and the best flavor before serving.