Heat the water: Bring 1/2 cup of water to just off a boil. You want it hot but not raging to avoid bitterness.
Steep the tea: Add the Earl Grey to a mug and pour in the hot water.
Steep for 3–4 minutes for bags or 2–3 minutes for loose leaf. Remove the bags or strain.
Warm the milk: In a small pot, heat 1 cup milk over medium until steaming with tiny bubbles at the edges. Don’t boil.
Flavor the milk: Stir in the vanilla and your chosen sweetener.
Taste and adjust. Add a tiny pinch of lavender or lemon zest if using, then remove them after 30 seconds.
Froth it: Use a handheld frother, whisk vigorously, or shake the warm milk in a jar with a tight lid for 20–30 seconds to foam.
Combine: Pour the flavored milk into the mug with the strong tea, holding back some foam. Spoon the foam on top.
Finish: Dust with a pinch of cinnamon or a microplane swipe of lemon zest if you like.
Sip while hot.