1. Mix the flour, sugar and salt together in a mixing bowl and rub the butter into the flour. The mixture should resemble breadcrumbs.
2. Mix together the vanilla extract, egg yolks and water and add to flour mixture. Knead together to a smooth dough. Wrap up in a plastic film and refrigerate for at least 30 minutes.
3. Lightly grease a 24cm (9 inches) round dish.
4. Preheat the oven to 180°C (350°F).
5. Roll out the pastry on a lightly floured board to 3mm (1/10 inch) thickness, so it is sightly larger than the 24cm (9 inches) round dish. Carefully line the dish and trim off excess pastry.
6. Spread the apricot preserve over the base of the tart. Decorate the top with pastry off-cuts.
7. Place the tart in oven preheated to 180°C (350°F) and bake approximately 20-30 minutes (until the pastry is golden brown).
8. Allow to cool down before serving.