Preheat oven to 160°C/140°C fan-forced. Grease a 6cm-deep, 19cm square cake pan. Line base and sides with baking paper, allowing a 5cm overhang.

Place biscuits in a processor. Process until fine crumbs form. Add butter. Process until combined. Press mixture into base of prepared pan. Refrigerate for 30 minutes.

Meanwhile, make caramel: Place caramels and cream in a small saucepan over medium-low heat. Cook, stirring, for 2 to 3 minutes or until smooth. Remove from heat.

Using an electric mixer, beat cream cheese, sugar and vanilla until smooth. Add eggs, 1 at a time, beating after each addition. Beat in cream and flour until just combined.

Pour mixture into prepared pan. Place spoonfuls of caramel on cheese mixture. Using a wooden skewer, swirl through caramel. Bake for 50 minutes or until centre is almost set. Cool in oven for 3 hours with door slightly ajar. Refrigerate overnight.

Make caramel sauce: Place sugar, cream and butter in a saucepan over medium heat. Cook, stirring, for 4 to 5 minutes or until boiling. Reduce heat to low. Simmer for 2 minutes or until slightly thickened. Remove from heat. Set aside for 10 to 15 minutes to cool slightly. Serve cheesecake with caramel sauce.