Roll the pastry out to the thickness of a £1 coin, about 4cm (1.5 inches) wider than the tin you’re lining. (If it’s a deep tin, you’ll need to roll it wider.)
Use the rolling pin to lift the pastry and help you position it over the tin.
Press the pastry in using your fingertips and then push it into the corners using a rolled-up ball of pastry trimmings which you have dusted with flour.
Leave an overhang of pastry around the sides of the tin.
Prick the base of the pastry case all over with a fork.
Heat oven to 200C/180C fan/gas 6 or the stated temperature for the recipe you are using.
Line the tart tin with baking parchment and fill with ceramic baking beans or dried pulses.
Bake for about 15 minutes or until the pastry is firm, then remove the beans and cook for about 5 minutes more, until golden brown and biscuity.
Trim off any excess using a small serrated knife before filling.