Mango and lemongrass milkshake
Smash the lemongrass in a pestle and mortar until its aromas are released.
Boil half of the milk and add the lemongrass. When the infused milk has cooled to room temperature, remove the lemongrass and discard.
Place the milk in a blender, together with the other ingredients and the remaining cold milk. Whiz until smooth.
Pour into a tall glass to serve.