Combine all the ingredients together in a large mug with a fork.
Microwave for 2 Minutes, keeping a close eye to make sure it doesn't overflow.
Take out and stir vigorously for 30 seconds.
Leave to cool for 1 Minute.
Cook for a further 2 Minutes, keeping a close eye. Leave to cool slightly before eating, top with banana, nondairy yoghurt, or nuts if desired. The top should be nice and crisp just like if it were baked!