Beat butter and sugar for 2 mins until light and fluffy in mixer longer by hand
Add egg yolk 1 at a time then add vanilla extract or essence for a further 30 seconds
Add sifted flour gradually to mix while beating very slowly then knead together on cold bench for 30 seconds
Add a dusting of flour and cut into 2 pieces and gently flatten by hand so it’s easier to roll, wrap in cling film and refrigerate for an hr before rolling.
Remove from fridge and roll to required thickness, cut and bake in a preheated oven at about 150degrees C until golden. Depending on thickness,.. about 12-16 mins. Cool and sprinkle with some caster sugar if required