Pât&eacute sucrée (Sweet biscuit pastry)

1. Sift flour and salt onto a marble slab or working surface. Make a well in the middle, moving flour away from centre. Place butter, castor sugar, egg yolks and vanilla essence in the well.
2. Using fingers of one hand in a pecking motion, soften and gradually combine ingredients in centre until well mixed. It is important to mix centre ingredients well before incorporating flour; use the fingertips because they are cooler than the palms of your hand.
3. Using a palette knife in the other hand, draw in flour and cut into the butter mixture. It should resemble coarse yellow breadcrumbs. Draw dough together and knead until smooth. It is easy to overwork, so take care!
4. Wrap in plastic wrap and chill for at least an hour.