01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - Whisk together flour, baking powder, salt, and ground Earl Grey tea leaves in a medium bowl.
03 - Beat softened butter and granulated sugar with electric mixer until light and fluffy, approximately 2-3 minutes.
04 - Mix in egg, vanilla extract, lemon zest, and lemon juice until fully incorporated.
05 - Gradually add dry ingredients to wet mixture, mixing just until dough comes together.
06 - Scoop tablespoon-sized portions of dough, roll into balls, and coat each ball in granulated sugar.
07 - Place sugar-coated dough balls 2 inches apart on prepared baking sheets.
08 - Bake for 10-12 minutes until edges are lightly golden while centers remain slightly soft.
09 - Let cookies rest on baking sheet for 5 minutes before transferring to wire rack to cool completely.