Preheat your oven to 160ºC (325ºF) and line the bottom of a 22 cm springform tin with parchment paper.

Combine digestive or graham crackers, dark brown sugar, ground cinnamon, and ground nutmeg in a food processor. Pulse until finely crumbed, then blend with melted butter. Press into the springform tin and bake for 10 minutes. Cool completely.

Peel, core, and dice apples. Toss with granulated sugar and cinnamon, then set aside.

Mix all-purpose flour, dark brown sugar, and cold butter in a bowl until crumbly. Set aside.

Beat cream cheese until smooth, gradually adding sugar, sour cream, and cornstarch. Add eggs one at a time, mixing well.

Pour the cheesecake batter over the cooled crust. Spread the apple mixture over the batter, then sprinkle with crumble topping.

Place the springform pan in a larger dish with hot water and bake for 1 hour and 20-30 minutes until edges are set.

Let the cheesecake cool inside the oven for 1 hour, then cool at room temperature for an additional hour. Refrigerate for at least 6 hours, preferably overnight.