Heat milk until it is warmed (do not boil). Whisk vanilla and sugar into to the warm milk. If serving an iced latte, this step can be done ahead of time. Refrigerate sweetened milk for up to 3 days before proceeding.Next, use a handheld milk frother to whip until foamy. Set aside.
Prep the Matcha:
Use a saucepan or tea kettle to heat water to 170 degrees Fahrenheit.Pour a little of the heated water into a small bowl to warm it. Then drain and dry the bowl.Scoop matcha powder into the sieve, and use a spoon to gently sift all the matcha into the small bowl.
Pour 3 or 4 ounces of heated water over the matcha.Whisk the matcha and the water for about 20 seconds with quick W-shaped motions until a foam develops.
Make the Latte:
Pour the milk mixture into the matcha.
For an iced latte, prepare a glass by filling with ice. For a hot latte, get a teacup or mug ready.Pour the combined milk and matcha mixture into the glass or mug, and serve right away.
Notes
Herbal tea layering: For some extra flavor, make a strong brew of herbal tea of your choice and add it to the latte for extra flavor. (I like this Butterfly Blue Pea Flower tea.)