I am an idiot and did not check I had enough cocoa before starting. Consequently I have used every last scrap for the cake (which is in the oven) but have none left for the icing.
I've tried googling but every result I have found seems to involve either double cream (don't have) or a mix of hot choc powder and cocoa.
The recipe I was going to use was cocoa powder, cream cheese, butter and icing sugar - and I have all of those things except the cocoa (obviously).
Help!