Preheat oven to 170C.

Cream softened salted butter and icing sugar until light and fluffy.

Combine egg yolks into the mixture.

Then, stir in plain flour and cornstarch.

Divide the dough into 3 and flavor them accordingly.

Transfer each dough into the respective piping bag with a star tip. Then, pipe out evenly onto a baking tray lined with parchment paper.

Bake it in the oven for 15 to 20 minutes until golden brown.

Let it cool completely before storing it into an airtight container.