Using a stand mixer on high speed (with the whisk attachment), cream together the butter, icing sugar and vanilla, until fluffy.
NOTE: If you are using a vanilla bean instead of the vanilla extract, slide a knife along the outside of the vanilla bean to reveal the centre, then gently scrape out the centre of the bean, then add the centre to the ingredients as listed above. Don't add the bean pod.
Add the flour, then beat for 10 minutes.
At this point you will have to scrape the sides of the bowl often to make sure all the ingredients are being whipped.
When the batter is ready, it should be white and fluffy.
Drop the cookie dough by the tablespoonful onto a parchment paper lined cookie sheet.
Bake for 10 minutes, careful not to let them brown.