Preheat the Oven and Prepare the Baking Sheet. Preheat your oven to 350°F. Line a baking sheet with parchment paper or a silicone baking mat to prevent sticking and ensure even baking.
Cream the Butter and Sugars. In a large mixing bowl, beat together the softened butter, granulated sugar, and brown sugar until the mixture is light and fluffy. This should take about 2-3 minutes using an electric mixer.
Add the Egg and Vanilla Extract. Next, add the egg and vanilla extract to the butter mixture. Beat until well combined. The egg helps bind the ingredients, and the vanilla enhances the flavor of the cookies.
Combine Dry Ingredients. In a separate bowl, whisk together the flour, matcha powder, baking powder, and salt. Make sure the matcha powder is evenly distributed throughout the dry ingredients to avoid clumps in the dough.
Mix Wet and Dry Ingredients. Gradually add the dry ingredients to the wet ingredients, mixing just until combined.
Scoop the Dough. Use a cookie scoop or tablespoon to portion out the dough. Roll the dough into balls and place them on the prepared baking sheet, leaving about 2 inches of space between each cookie.
Bake the Cookies. Bake the cookies in the preheated oven for 10-12 minutes or until the edges are golden brown. The centers will still be soft, but they will firm up as they cool.
Cool and Enjoy. Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.