Sift the flour with pinch of salt in a large bowl. Rub in the butter until you have a soft breadcrumb texture.

Add enough cold water to make the crumb mixture come together to form a firm dough, and then rest for 30 minutes in the fridge.

Roll out the pastry on a floured surface and line a well buttered flan dish, don't trim the edges yet.

Remove from fridge again and prick base with a fork, then line with greaseproof paper and fill with baking beans.

Place in preheated oven Gas mark 5, for 20 minutes, then remove beans and paper and put back in oven for another 5 minutes.