Let the cookies cool for a few minutes before eating.
Store the cookies in an air-tight container. If there are still any leftovers after two days, I suggest microwaving the cookies for about 10 to 15 seconds before eating. This softens the cookie and melts the chocolate chips again.
Notes
Shaping the cookie dough in my hands and flattening it with my fingers worked for me. I tried using a glass cup to flatten the cookies on the baking sheet, but the dough kept sticking to the glass.
The green tea matcha powder has a slightly bitter taste. Add a few more tablespoons of sugar if you want to balance out the matcha flavor.