Open Earl Grey tea bags carefully. Grind tea leaves into fine powder using spice grinder or mortar.

In medium bowl, combine flour, ground tea, baking powder and salt. Stir until evenly mixed.

In large bowl, beat softened butter and sugar until light, fluffy, and pale in color.

Add egg and vanilla extract. Beat again until mixture becomes smooth and creamy.

Slowly add dry ingredients into wet mixture. Mix gently until soft dough forms.

Pour milk into dough. Mix lightly until dough becomes smooth and easy to shape.

Cover bowl with plastic wrap. Chill dough in refrigerator for thirty minutes for better texture.

Preheat oven to 350°F. Line baking tray with parchment paper.

Scoop small dough portions. Roll into balls and place evenly on prepared baking tray.

Press each ball gently with fingers or fork to flatten slightly.

Bake for ten to twelve minutes until edges turn lightly golden.

Let cookies cool on tray five minutes. Transfer to rack and cool completely.

In small bowl, mix powdered sugar, milk, and vanilla until smooth and slightly thick.

Drizzle glaze over cooled cookies. Let glaze set for fifteen minutes before serving.

Now you clearly understand How to make London Fog Tea Cookies at home.