Preparation:
Prepare the dough
Mix the flour, icing sugar, ground Earl Grey tea and salt in a bowl. Add the butter cubes and work into a crumbly dough using your fingers or a mixer.
Tie the dough
Add the egg yolk and vanilla extract and knead the dough into a smooth mass. Wrap the dough in cling film and leave to rest in the fridge for at least 30 minutes.
Preheat the oven
Preheat the oven to 180 °C (top/bottom heat). Line a baking tray with baking paper.
Shaping the cookies
Roll out the dough on a floured work surface to a thickness of approx. 5 mm. Cut out round shapes with a biscuit cutter and place on the baking tray.
Baking
Bake the cookies in the preheated oven for approx. 10-12 minutes until lightly golden brown. Leave to cool completely on a wire rack.
Glaze (optional)
Mix the icing sugar with the lemon juice to make a smooth icing and decorate the cookies as desired.