Preheat the oven to 180`c. To make the torte, crush the bourbon biscuits into crumbs and place into a bowl. Pour over the melted butter. Press into a 20cm/8in spring-form cake tin to form the base. Place the chocolate in a bowl over barely simmering water and melt, making sure the water doesn’t touch the bottom of the bowl. Place the cream cheese, ricotta and sugar in a food processor and blend until smooth. Next add the eggs, then the cocoa powder, melted chocolate and mincemeat. Spoon the mixture onto the base and bake in the oven and cook for approximately 45 minutes, or until cake is springy to the touch. Allow to cool in the tin. Meanwhile, prepare the brandy sauce. Place the chocolate and cream in a clean bowl over a pan of simmering water and melt, making sure the water doesn’t touch the bottom of the bowl. When melted, whisk in the butter and brandy. The sauce must be prepared just before the cake is served, because it can’t be reheated. Serve large slices with a big spoonful of sauce and a dollop of clotted cream.