Place the flour in a large bowl and add the butter and fat. Rub in with your fingertips, lifting the crumbs up and above the ingredients.
Make a well in the centre of the bowl with a round bladed knife and add the water, bring the mixture together.
Turn the pastry out onto a lightly floured surface and lightly knead and then wrap in cling film and then flatten gently to a thick disc. Chill for 20 minutes.
Remove the cling film and then roll out on a floured surface to a circle measuring 22cm in diameter. Rotate the pastry as you roll to create a circle.
Fold the pastry into quarters and lift into the centre of the fluted flan case. Open out the pastry and using your knuckles ease the pastry in place. Roll a rolling pin over the pastry to neaten the rim. Prick the pastry base with a fork and chill again for 20 minutes.
Preheat the oven to 200°C, fan 180°C, gas 6. Line the pastry with a circle of greaseproof paper and then add the baking beans. Cook for 20 minutes. Carefully remove the paper and then bake the pastry for a further 10 minutes.