Soften butter at room temperature and whisk lightly.

Add condensed milk and milk to the butter and mix well.

Add cake flour and mix with a spatula until combined.

Form the dough into one ball and wrap in plastic. Rest for 1 hour. For green tea variation, divide the butter mixture into two portions before adding flour: one with 140g flour, the other with 130g flour + 1 tbsp green tea powder.

Roll the rested dough to a thickness of 5mm using a rolling pin.

Cut the dough into desired shapes using cookie cutters.

Arrange the cut dough neatly on a baking tray.