When making the rough puff pastry, make a double batch then wrap it well and freeze it for the next time you need it.
500g plain flour
1 tsp fine salt
1 tbsp sherry vinegar
50g unsalted butter, at room temperature
250ml cold water
350g unsalted butter, cold
Sift the flour and salt into a large bowl. Add the vinegar, soft butter and water and combine slowly by hand to form an elastic dough – don't over-mix. Form the dough into a ball, then cover with plastic wrap and refrigerate for two hours.
On a lightly floured bench, roll the pastry out into a 30-centimetre square. Shape the cold butter into a 15-centimetre square and place in the centre of the pastry. Using a knife, make a cut from the corner of the butter to the corner of the pastry, then fold the pastry over the butter to completely enclose it.
Using a rolling pin, gently but firmly work the dough and butter into a 45-centimetre x 15-centimetre rectangle, keeping the butter between the layers of dough.
Fold the dough into thirds then place on a plate, cover with plastic wrap and refrigerate for 25 minutes.
Place the dough on the floured work surface with the folded edge facing you. Roll out to 45 centimetres x 15 centimetres again, fold into thirds, cover and refrigerate for 25 minutes. Repeat this process three more times and place in the fridge to rest.