Divide the butter into 4 equal portions. Chill 3 portions.

Sift flour and salt into a bowl. Rub in the unchilled portion of butter. Mix to a soft dough with water and lemon juice. Turn out on to a floured work surface. Knead thoroughly. Put into a polythene bag or wrap in aluminium foil. Chill for 30 minutes.

Roll out on a floured work surface into a 0.5 cm (1/4 inch) thick rectangle, measuring about 45 x 15 cm (18 x 6 inches). Using the tip of a knife, dot the second portion of butter (in small flakes) over the top and middle thirds of the rectangle to within 2.5 cm (1 inch) of the edges. Dust lightly with flour.

Fold in 3 by bringing the bottom third over the middle third and folding the top third over. Seal the open edges by pressing firmly together with a rolling pin. Put into a polythene bag or wrap in aluminium foil. Chill for 15 minutes.

Remove from the bag or unwrap. With folded edges to left and right, roll out again into a 45 x 15 cm (18 x 6 inch) rectangle. Cover with third portion of butter as before. Fold, seal and chill. Repeat again, adding last portion of butter and chill.

Roll out again. Fold and seal, return to the polythene bag or aluminium foil. Chill for at least 30 minutes before rolling out to 0.5 cm (1/4 inch thickness and using. After shaping, let dishes rest 30 minutes before baking.

Wrap the pastry loosely in greaseproof paper and leave it to 'rest' in the refrigerator or a cool place tor at least 30 minutes before using.

Roll out the pastry on a lightly floured working surface to 0.3 cm (1/8 inch) thick and use as required. Brush with beaten egg before baking to give the characteristic glaze.

To cook, bake at 200°C (400°F) gas mark 6, unless otherwise stated.