01 -
Preheat oven to 320°F (fan). Lightly grease an 8 x 8-inch baking pan and line with baking paper, leaving overhang for easy removal.
02 -
Pulse digestive biscuits in a food processor or crush in a sealed bag until fine crumbs form. Combine crumbs with melted butter until mixture looks like damp sand. Press evenly into the base of prepared pan and chill.
03 -
Beat cream cheese in a mixer until smooth and fluffy. Add sugar, salt, and vanilla extract, mixing to incorporate. Add eggs one at a time, beating well after each addition. Scrape bowl sides as needed.
04 -
Remove crust from fridge and pour cheesecake batter over it, spreading evenly. Tap pan gently on surface to remove air bubbles.
05 -
Combine diced apples with sugar, lemon zest, cinnamon, and nutmeg in a large bowl. Stir to coat and let rest for 5 minutes.
06 -
Rub chilled butter into flour, cinnamon, demerara sugar, and granulated sugar until mixture is coarse and breadcrumb-like.
07 -
Spread spiced apples evenly over cheesecake layer. Top with crumble mixture in an even layer.
08 -
Bake for 45 to 50 minutes, until crumble is golden and filling is set. Allow to cool completely at room temperature, then refrigerate for at least 3 hours or overnight.
09 -
Use parchment paper overhang to lift bars from pan. Drizzle with caramel sauce, slice into portions, and serve.