Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, beat together the softened butter and sugar until the mixture is light and creamy, and the sugar begins to dissolve, about 2-3 minutes and smelling sweet.
Crack in the egg and continue to beat, ensuring it's fully incorporated and the mixture becomes smooth and slightly fluffy.
In a separate bowl, whisk together the flour, baking powder, salt, and matcha powder until evenly combined.
Gradually add the dry ingredients to the wet mixture, folding gently with a spatula until the dough starts to come together, thick yet soft.
Puree the fresh strawberries in a food processor or blender until smooth, then gently fold the strawberry puree into half of the cookie dough, creating a pink marbled effect.
Take small dollops of the plain green dough and pink strawberry dough, and gently fold and twist them together just enough to create a marbled swirl—don't overmix to keep the streaks distinct.
Using a spoon or scoop, place balls of the marbled dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake in the preheated oven for 12-15 minutes or until the edges turn golden while the centers remain soft and slightly puffy.
Remove the cookies from the oven and let them cool on the baking sheet for about 5 minutes, then transfer to a wire rack to cool completely—they'll firm up as they cool.
Enjoy these cookies once cooled—they should be tender with a slight chew, showcasing beautiful swirls of pink and green with a fragrant strawberry-matcha aroma.
