1. Preparing the Dough

1. In a large mixing bowl, beat softened butter and sugar together until light and fluffy.
2. Add the egg and vanilla extract, mixing until well incorporated.
3. In a separate bowl, whisk together the flour, baking powder, and salt.
4. Gradually add the dry ingredients to the wet mixture, mixing until a soft dough forms.
5. Divide the dough into two equal portions.

2. Creating the Matcha Layer

1. Take one half of the dough and mix in the matcha powder.
2. Add 1–2 tbsp of heavy cream, as needed, to ensure a smooth and even consistency.
3. Leave the other portion plain for the vanilla layer.

3. Marbling the Dough

1. Take small portions of both the matcha and vanilla dough.
2. Gently twist or fold them together to create a marbled effect.
3. Roll into balls and flatten slightly onto a parchment-lined baking sheet.

4. Baking the Cookies

1. Preheat your oven to 350°F (175°C).
2. Bake for 10–12 minutes or until the edges are slightly golden.
3. Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack.