Preheat your oven to 205ºC (400ºF). Slice peaches into thin wedges and toss with granulated sugar and ground cinnamon. Bake for 15 minutes until softened.

In a mixing bowl, combine all-purpose flour and dark brown sugar. Melt some butter and pour over the mixture, stirring until crumbly.

Lower oven to 160ºC (325ºF). Blend digestive or graham crackers with granulated sugar until finely crushed. Mix in melted butter and press into the bottom of a lined springform pan. Bake for 10 minutes.

Beat cream cheese until smooth. Gradually add granulated sugar, sour cream, cornstarch, vanilla extract, and eggs, mixing until creamy.

Pour half of the cheesecake batter into the crust. Layer half of the baked peaches, then add remaining cheesecake batter and top with remaining peaches and crumble.

Place the springform pan in a larger roasting pan filled with hot water. Bake for 85–95 minutes until the center is slightly wobbly but mostly set.

Turn off the oven and crack the door open, allowing the cheesecake to cool slowly for 1 hour. Cool completely at room temperature, then refrigerate for at least 6 hours or overnight.