A perfect St Patrick`s Day treat

Info on the life of St Patrick and an ideal celebratory dessert provided via Head Chef of the Crown in Ripon Aaron Craig in conversation with Alex Lewczuk, Dave Kenyon & Rebecca Friis-Jansen ( original TX for The Midweek Drive Morning Edition on Thursday March 17th 2011 ) recipe details reproduced below Guinness and Chocolate Cake     FOR THE CAKE 250ml Guinness 250g unsalted butter 75g cocoa 400g caster sugar 1 x 142ml pot sour cream 2 eggs 1 tablespoon real vanilla extract 275g plain flour 2 1/2teaspoons bicarbonate of soda FOR THE TOPPING: 300g Philadelphia cream cheese 150g icing sugar 125ml double or whipping cream   Preheat the oven to gas mark 4/180°C, and butter and line a 23cm springform tin. Pour the Guinness into a large wide saucepan, add the butter - in spoons or slices - and heat until the butter's melted, at which time you should whisk in the cocoa and sugar. Beat the sour cream with the eggs and vanilla and then pour into the brown, buttery, beery pan and finally whisk in the flour and bicarb. Pour the cake batter into the greased and lined tin and bake for 45 minutes to an hour. Leave to cool completely in the tin on a cooling rack, as it is quite a damp cake. When the cake's cold, sit it on a flat platter or cake stand and get on with the icing. Lightly whip the cream cheese until smooth, sieve over the icing sugar and then beat them both together. Or do this in a processor, putting the unsieved icing sugar in first and blitz to remove lumps before adding the cheese. Add the cream and beat again until it makes a spreadable consistency. Ice the top of the black cake so that it resembles the frothy top of the famous pint.