These are basically a sort of brioche doughnut version of everyone's favourite stout cake. We've even stuffed them with a sweetened mascarpone cream. Give them a try - you won't regret it!
Whisk the flour, cocoa powder, baking powder, caster sugar. If you want your doughnuts to be jet black, like a Guinness!
Rub the butter into the mixture until it resembles fine bread crumbs, then mix in the eggs and the Guinness or other stout. Give it a knead for around 5 minutes, then leave it to rise until doubled in size.
Punch it down and divide into 14 or so even sized balls. Roll them on a floured surface to make them taught and round. Let them rise for around 1 - 2 hours, until doubled in size but not sagging.
Heat the oil until it's around 170°C. Fry the doughnuts in batches, keeping a watchful eye on the temperature - as the doughnuts are so dark it's hard to tell if they are burning. Flip them after 3 minutes and cook for another 3 mins on the other side. Remove and toss them through the sugar.
Whip together the cream, sugar and mascarpone. Pipe this into the middle and scatter with Oreo crumbs.