Preheat your oven to 180°C (350°F). Line a baking tray with parchment paper.

In a medium mixing bowl, whisk together flour, matcha powder, baking soda, and salt.

In a large mixing bowl, cream the butter and sugar using the hand mixer until light and fluffy, about 2 minutes.

Add the egg and vanilla extract to the butter-sugar mixture and mix until combined.

Gradually add the dry mixture to the wet mixture, mixing on low speed until just incorporated.

Melt the white chocolate chips in a small microwave-safe bowl in 20-second intervals, stirring between each, until smooth.

Gently fold the melted white chocolate into the dough, creating streaks rather than fully mixing.

Use a tablespoon or cookie scoop to scoop out 16 heaped portions of dough onto the baking tray, spaced evenly.

Bake for 9–10 minutes, or until the edges are set but the centers remain soft.

Cool on the baking tray for 2 minutes, then transfer cookies to a cooling rack to cool completely.