How to make:

1. Mix butter and granulated sugar, beat with a mixer on high speed until the mixture becomes creamy (pale in color).
2. Add the egg, mix well.
3. Add the lemon zest, mix well.
4. Add lemon juice, mix well.
5. Sift the flour, vanilla powder, and baking powder, then add to the mixture, and stir using a spatula.
6. Chill the dough in the refrigerator for about 1 hour until it hardens.
7. Preheat the oven, use both top and bottom heat at 180 °C.
8. Take the dough out of the refrigerator, weigh it into 15-gram portions.
9. Roll the dough into balls, then coat with icing sugar until fully covered.
10. Bake the dough until cooked.

Yields 30 pieces.