Preheat the oven to 325°F (160°C) and gather baking equipment, including a 9-inch springform pan.

In a food processor, pulse the digestive biscuits with cinnamon and sugar until fine. Blend in melted butter and press into the bottom of the springform pan. Bake for 10 minutes and let cool.

Mix dark brown sugar and cinnamon in a small bowl for the cinnamon sugar layering.

In another bowl, whisk together all-purpose flour and dark brown sugar. Stir in melted butter to form coarse crumbs for the topping.

Beat cream cheese in a stand mixer until smooth. Gradually add sugar and combine until smooth.

Combine sour cream and cornstarch in a bowl, then add to the cream cheese mixture along with the eggs, mixing until just incorporated.

Pour half the cheesecake batter over the cooled crust and sprinkle with half of the cinnamon sugar. Repeat with remaining batter and finish with crumble topping.

Place the springform pan in a larger baking dish filled with hot water. Bake for 1 hour and 15-20 minutes until the center is slightly wobbly.

Turn off the oven and leave the cheesecake inside with the door ajar for 1 hour, then refrigerate for at least 6 hours.

Run a knife around the edges of the pan before releasing it. Serve with whipped cream or vanilla ice cream.