To cook in the microwave, spoon the mixture into the pudding basin until three-quarters full, then smooth the surface with the back of a spoon. Loosely cover with clingfilm (allow room for the clingfilm to inflate as the mixture rises) and place in the microwave for five minutes. The pudding is done when a skewer inserted into the centre comes out clean. Leave to stand for five minutes, before turning out onto a deep plate and remove the basin.