To prepare the dough, in a large bowl whisk together the flour, sugar and salt. In a separate bowl whisk together the egg yolk, vanilla and ice water. Slowly pour into the flour mixture, mixing until combined. Cut the butter into the mixture with a pastry blender until pea-size clumps form. Knead the dough into a ball, then pat flat and wrap with plastic wrap. Refrigerate for 1 hour.