100g dark chocolate, roughly chopped
150g McVitie’s dark chocolate biscuits, crushed
30g butter, melted
200g tub Philadelphia cream cheese
220g caster sugar
3 eggs
1 tsp vanilla extract
90g plain flour
1tsp baking powder
1 tbsp cocoa
120ml cream, whipped
Icing sugar
Grated chocolate to decorate

Preheat the oven to 180ºC and line a 20-cm square cake tin or baking dish with non-stick baking paper.

Melt the chocolate either in a microwave or over hot water and leave it to cool. Mix the biscuit crumbs with the melted butter, then spread them in the bottom of the cake tin, patting them out evenly.

Beat 120g of the cream cheese with a little of the sugar until fluffy. Gradually beat in the rest of the sugar and the eggs, one at a time, then stir in the vanilla extract and melted chocolate. Sift together the flour, baking powder and cocoa and fold them in to the chocolate mixture, stirring until they are well combined, then pour the mixture into the cake tin and bake for about 35 minutes, or until a cocktail stick inserted in the centre comes out fairly cleanly. Cool in the tin, then turn out on to a serving plate.

Beat the remaining cream cheese until light and fluffy and fold it into the whipped cream, then sweeten to taste with sifted icing sugar.

Swirl on top of the cake and scatter over the grated chocolate.Cut into squares and serve with ice-cream. (Cuts into nine squares)