Preheat the oven to 350. Cover a half sheet tray with a piece of parchment paper and set aside.
Add the egg, melted butter, and vanilla extract to the cookie mix and stir to combine.
Divide the dough in half in two separate bowls. Mix one tablespoon of matcha into one of the doughs, stirring carefully so as not to mix in completely.
Add the matcha flavored dough into the plain dough, then use your hand to mix, being careful not to over mix.
In a small bowl, combine the remaining matcha with the granulated sugar. Set aside.
Using a cookie scoop, scoop out portions of the dough and roll them into a circle using your hands. Roll each cookie in the matcha and sugar mixture until coated, then move to the cookie sheet. Repeat for all cookies.
Chill for 15 minutes, then bake for 10. Don't over bake these—the goal is to get a gooey center!
