First find a suitable cup or mug into which the (Iced) Chai Latte will later be filled. Hang the tea bag in this cup and fasten it.
Now measure the milk and bring to the boil in a saucepan (don`t forget to stir to avoid burning). Pour the milk into the bag in the cup and add the sugar (or agave syrup) and the vanilla (can be left out, but I recommend it to everyone), then stir well.
Remove the tea bag from the cup before serving. For warm days I recommend adding ice cubes for an Iced Chai Tea Latte.