Heat oven to 180c/fan 160c/gas 4. Roll out 375g pack shortcrust pastry, then use it to line a 23cm loose-bottomed tart tin. Line with non-stick baking parchment and baking beans, then bake for 15 minutes. Remove the beans, then bake for 10 minutes more until golden. Remove from the oven, then reduce the heat to 140c/fan 120c/gas 1.