Preheat the oven to 180c/160c fan oven and grease and line two 23cm cake pans.

In a large saucepan, over a medium heat melt together the butter and guinness. When it's melted remove from the heat and and add in the sugar and cocoa, whisk until combined.

in a separate bowl whisk together the eggs, vanilla and sour cream. Then pour this mixture into the the saucepan and stir again.

Finally sift in the flour and bicarb and fold into the mixture. When it is well mixed divide the batter between the two pans and bake in the oven for 45-50 minutes or until a skewer inserted into the centre of the cake comes out clean.

Remove the cakes from the oven, leave for 5 minutes and then while they are still warm poke the surface of the cakes with the handle of a wooden spoon and spoon over half of the caramel sauce so it soaks down into the holes. If your sauce is a little thick heat it in the microwave for 10 second intervals until it is runny and pourable. Leave the cakes to cool completely.

In the bowl of your mixer beat the cream cheese until smooth then sift in the icing sugar and cornflour. Beat again for a minute or so then pour in the cream. Beat until it has thickened and is light and fluffy.

Place one cake layer onto a cake stand or plate and spread half the cream cheese frosting over the surface of the cake. I used a piping bag fitted with a very small round nozzle to drizzle half the remaining salted caramel sauce in a criss cross over the frosting. Again, you might need to heat your sauce a little if it is too set. Repeat this process with the second cake layer and the rest of your frosting and sauce and you're all done. Cake heaven!! Try not to eat too many slices :)