
In a medium bowl whisk together the flour, baking powder and salt.
In a large bowl or stand mixer, beat the yolks and sugar for 2-3 minutes. Add the zest, vanilla and butter, beat to combine, add the dry ingredients and combine on low, 1 minute. Cover the bowl and chill 30 minutes.*
Form the dough into balls (golfball size) and place on 1-2 parchment paper lined baking sheets, lightly flatten with a fork or the bottom of a glass. Chill while the oven is pre-heating to 350F / 180C. Bake for approximately 12-15 minutes or until lightly golden. Let cool on the baking sheet for approximately 15 minutes then move to a wire rack to cool completely. Dust with powdered sugar before serving. Enjoy!