1. Add butter and sugar to a large bowl and mix until light and fluffy. Next, add the egg and vanilla extract and mix until well combined. Add the sweetened red bean paste and mix in. If you want to use food color, add several drops and mix until well distributed. Combine flour, baking powder, and salt, then add the dry ingredients to the bowl and mix until just combined – we normally do that with a rubber spatula only. Wrap the dough in plastic wrap and place it in the fridge overnight.

2. Preheat the oven to 350°F (180°C). Line a baking sheet with baking parchment and set aside. Have two bowls ready – one with the sugar and one with the confectioners’ sugar for the coating. Divide the dough into about 22 pieces, with about 30g (1 oz.) each. Shape each piece of dough into a small ball and roll it first in the sugar, then in the confectioners’ sugar. You want the layer of confectioners’ sugar to be quite generous, or the cracks in the surface will not show after baking. Place the covered balls with enough space in between on the prepared baking sheet (we could fit max. 12 on a baking sheet). Bake the cookies for about 10 minutes – you want to see big cracks all over the cookies.

3. Take the cookies out of the oven – if the cookies have spread a lot, you can bring them back in shape right after baking with a round cookie cutter. Just swirl them lightly inside the cookie cutter to give them their round shape back. Let the cookies cool down on the baking sheet until they can be moved (they are quite soft when warm). Transfer the cookies to a wire rack and let cool down completely. Repeat the process with the remaining dough.