Grease a 20cm base square cake tin. Line base and sides with baking paper, allowing a 3cm over hang on all sides.
To make the biscuit base: Process biscuits until it resembles fine crumbs. Add melted butter. Process until combined.
Tip mixture into prepared tin, using the back of a metal spoon, press mixture over base of prepared tin. Refrigerate for 15 minutes.
To make caramel filling, place 50g butter and condensed milk in a small saucepan over medium- low heat. Heat stirring constantly for 10- 12 minutes or until mixture thickens and becomes golden.
Pour over base, with the back of a metal spoon, smooth top. Refrigerate for 10 minutes.
To make the chocolate topping: place chocolate and cream in a bowl over a small pot of boiling water. Stirring constantly for 5 minutes or until melted.
Spread chocolate over filling. Cover and refrigerate for 3 hours or until set.
Cut into pieces and serve.