Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper.
Add the Earl Grey tea to a food processor and pulse until finely ground. Pass through a sieve to separate any large bits.
3 tbsp (12 g) Earl Grey tea
In a medium bowl, whisk together the flour, baking powder, baking soda, salt and ground Earl Grey tea. Set aside.
2 3/4 cups (344 g) all purpose flour, spooned and leveled (please see notes), 1/2 tsp baking powder, 1/2 tsp baking soda, 1/2 tsp salt
Add the sugar and softened butter to a bowl. Cream together with an electric mixer on high speed for 1-2 minutes until very light and fluffy.
1 cup (200 g) granulated white sugar, 1 cup (227 g) unsalted butter, softened
Add in the egg and vanilla and mix on medium speed until pale in color and very fluffy, about 1-2 minutes.
1 egg, at room temperature, 2 tsp vanilla bean paste
Add in the dry ingredients. Mix on low speed just until combined.
Scoop the dough with a 2 tbsp cookie scoop, and roll them into balls. Then roll the dough balls in the lavender sugar.
Place the cookie dough balls at least 2 inches apart on the baking sheets. Slightly flatten each ball and form into a circle as best as you can.(See photo in the blog post above.)Bake 6-8 cookies at a time. Bake the cookies for 9-10 minutes, then let them cool on the baking sheet for 5 minutes.(When the cookies are straight out of the oven, scoot a large circular cookie cutter around them to give them a perfect circular shape.) Transfer the baked cookies to a cooling rack to finish cooling.