Put the butter and icing sugar in the mixer and cream until light and fluffy.

Add the egg, and when emulsified, add the flour and custard powder.

Mix less than 1 minute, just enough for the dough to come together. Do not overmix.

Shape them into 1/2 teaspoon round balls.

Coat with sugar.

Press each ball with a fork.

Bake at 180C for 15 minutes.

Cookie is very light in color and melts in the mouth.