Can I Stop The Frosting On The Chocolate Guinness Cake From Drying Out?

Our answer

Nigella's Chocolate Guinness Cake (from FEAST) is topped with a billowing cream cheese frosting that emulates the frothy top of a pint of Guinness. Most frostings will start to "crust" a little as they stand, and this will also happen to the frosting on this cake. Unfortuately as the frosting needs to be refrigerated, due to the whipped cream, it will dry out more easily and the best way to try and prevent this is to keep the cake in a tightly sealed airtight box in the fridge.

The cake itself gets its dark colour from the stout and cocoa powder. As the cake is quite moist and the frosting is quite damp, the colour of the cake will eventually start to bleed into the frosting. You would need to put a barrier between the cake and the frosting to prevent this from happening. You may be able to put a thin layer of chocolate ganache (made with equal quantities of cream and dark/bittersweet chocolate) on the top of the cake and let this set before putting the frosting on. However, we have not tried this ourselves so are unable to guarantee the results. If you intend to keep the cake for a couple of days then we would suggest storing the cake and frosting separately and adding some frosting to the top of each slice as you serve it. The cake without frosting can be kept in an airtight conatiner at room temperature for up to 5 days. The frosting will keep separately in the fridge in an airtight container for 2-3 days.