Dust a clean surface and a rolling pin with flour, then carefully roll out your pastry, turning it every so often, until it’s about 0.5cm thick (0.2″).
Carefully roll your pastry around the rolling pin, then unroll it carefully over your oiled tin.
Ease the pastry into the tin, making sure you push it into all the sides. Trim off any major excess by running a knife along the top of the pastry case, then prick the base of the case all over with a fork and pop it into the freezer for 30 minutes. Preheat your oven to 180ºC/350ºF/gas 4.