Matcha shortbread cookies

Line a baking sheet with parchment paper.

Place the butter and icing sugar in a large bowl. Using an electric mixer, beat until light and fluffy. Sift together the matcha, flour and corn starch, then gradually mix them into the butter mixture until a soft dough forms. Add a little extra flour, if needed.

Roll out the dough to ½cm thickness on a lightly floured surface. Using a cookie cutter, cut out shapes and place them on the baking sheet. Place the cookies in the refrigerator for 30 minutes to chill, so they maintain their shape while baking.

Preheat the oven to 180°C, gas mark 4.

Bake the cookies for 10-12 minutes or until the edges turn lightly golden. Remove from the oven and let them cool completely before filling.

To make the ganache, chop the white chocolate and place it in a heatproof bowl. Heat the cream and ube powder (or strained blackberry jam) until steaming, then pour over the chocolate. Allow it to sit for 5 minutes before stirring until smooth. Allow the ganache to set at room temperature, then whisk for approx. 1-2 minutes until light and fluffy.

Assemble the cookies by spreading a generous layer of ganache on one cookie and topping it with another cookie to create a sandwich.