Crumble the biscuits in a bowl. Put the cocoa and sugar and the egg. Melt the butter and stir into the ground around a large mass. Put in a tin of 24 cm (cake pan) with baking paper and spoon inside the mass and push it to the right until it is firmly and cover it with foil. Then a night in the fridge and then you paste cut. This recipe has a delicious sweet taste.