200g unsalted butter, 300g caster sugar, 1 large egg, 275g self-raising flour, 75g cocoa powder, three BIG bars of chocolate (white, milk and dark), a splash of milk.
Throw your butter into a bowl and whizz it in the microwave for a few seconds to soften, take out and add in the sugar. Mix with a spoon or electric whisk until creamy. Crack in an egg and mix some more, then throw in your dry ingredients: self-raising flour (no need to sift), cocoa powder and chocolate bars broken down into squares. Things might seem a little dry at this point so lug in a few drops of milk to combine the mixture into more of a dough if needed. Line two trays with baking paper, scoop the mixture into 12 handfull size balls and place far apart on the tray. Pop in a preheated fan oven at 220°C (200°C for non-fan) for 10 minutes. They will be super sloppy still when you remove them, but leave them to cool for around 30 minutes (if you can wait that long!), and they will stiffen up ready for your cookie eating pleasure.