Cut the mango down either side of the flat stone, then peel and cut the flesh into chunks.
Peel and chop the banana.
Put all the ingredients into a food processor or blender, then process until smooth and thick. Keep in the fridge and use the day you make it.
For an even quicker smoothieSimply replace the fresh mango with 250g/9oz frozen mango or mixed tropical fruit, available in most supermarkets. Frozen berries will also work brilliantly.