Melt the milk chocolate and 3/4 can of condensed milk in a bowl over simmering water, stirring occasionally.

Melt the white chocolate and remaining condensed milk in a separate bowl over simmering water, stirring occasionally.

Let both chocolate mixtures cool completely.

Crush the digestive biscuits into fine crumbs using a rolling pin or food processor.

Melt the margarine in the microwave for 40 seconds.

Mix the melted margarine into the biscuit crumbs until well combined and the mixture is sticky.

Press the biscuit mixture evenly into the bottom of a large flan dish.

Refrigerate the biscuit base to set while preparing the cheesecake filling.

In a large bowl, combine the 200g mascarpone cheese, 400ml double cream, and 3 tbsp sugar.

Whisk with an electric mixer until the mixture is thick and forms soft peaks.

Gently fold in the cooled milk chocolate mixture until well combined.

Pour the milk chocolate filling over the prepared biscuit base.

Refrigerate for 3-4 hours to allow the middle layer to set.

Once the middle layer is set, mix together the cooled white chocolate mixture with the remaining 50g mascarpone cheese, 200ml double cream, and 1 tbsp sugar until thick.

Pour the white chocolate mixture onto the top of the cheesecake.

Carefully spread the white chocolate layer evenly.

Refrigerate for a further 3-4 hours or preferably overnight to fully set.

Once the cheesecake is fully set, slice and serve.