Rub the lard into the flour and salt in a large bowl until it reaches a breadcrumb consistency.
Mix in cold water with a palette knife until a dough forms, then knead briefly on a floured surface.
Shape the dough into a rectangular block, wrap in cling film, and chill for 30 minutes.
Flatten the butter between greaseproof paper until it is one-third the size of the pastry.
Roll the dough into a 16cm x 30cm rectangle on a well-floured surface.
Divide the dough visually into three sections and widen the centre section slightly.
Place the butter in the centre, fold the pastry edges over to enclose it, and form a square.
Roll the pastry out, fold into thirds, repeat once, then refrigerate for 30 minutes.
Roll and fold twice more, rest in the fridge for 10 minutes, then roll and fold twice again.
Ensure the pastry has been folded six times total until smooth and no longer streaky.