Heat the water in a pan until it starts boiling.
Turn off the heat, add the tea and let it steep for 5 minutes.
Meanwhile, heat the milk in a small pan (alternatively microwave) together with the vanilla pod, until steaming. Remove the vanilla pod and froth the milk.
Strain the tea, add the agave syrup, the milk and stir gently.
Pour the London Fog in your favorite mug and enjoy it.