In a large mixing bowl, whisk together all-purpose flour, baking powder, and salt until well combined.

In a separate bowl, cream the softened butter and granulated sugar together until light and fluffy. Add in the egg or plain yogurt and the sweet red bean paste, mixing until smooth.

Gently fold the dry ingredients into the wet mixture using a spatula until just combined.

Cover the dough with plastic wrap and refrigerate for at least 4 hours or overnight.

Preheat your oven to 325°F (160°C). Form the chilled dough into balls and roll in granulated sugar followed by icing sugar.

Place the coated dough balls on a lined baking sheet and bake for 8-10 minutes until the edges are set.

Transfer the cookies to a wire rack to cool and dust with additional icing sugar before serving.