In a stand mixer bowl, mix butter and sugar for about 4 minutes. You should have a light colored and fluffy mixture.
Add the egg, one a time and scraping the sides after each egg.
In a medium bowl, sift the flour, matcha powder, baking powder and salt together.
While the mixer is on a low speed, slowly add the dry mixture into the butter mixture. Scrape the sides and mix again until the mixture comes together. Do not overmix.
Chill the dough overnight.
After the dough is chilled, take them out of the fridge for about 10 minute. This will make it easier to roll the dough into balls.
Preheat oven to 325 degrees Fahrenheit. Line your baking sheet with parchment paper.
With a medium size ice cream scoop, scoop the batter and then roll it into a ball. Place on the baking sheet. You need to work fast so that the batter won’t be too soft.
Bake for 12 – 15 minutes. You do want to check the bottom of the cookies so that it will be brown but still soft on top.