Put the pastry on a lightly floured kitchen bench and roll it out into a rectangle measuring 35 × 60 cm (133⁄4 × 231⁄2 in) and 4 mm (1⁄8 in) thick. Put the pastry (it’s quite long, so loosely roll it if needed) between two sheets of baking paper and refrigerate for 30 minutes.

Lay the pastry on a lightly floured bench with one long side parallel with the edge of the bench. Brush the entire sheet with egg wash. Sprinkle 60 g (2 oz) of the parmesan evenly over the bottom half of the pastry, followed by the rosemary, paprika, cayenne pepper, if using, and salt. Fold the top half of the pastry over the filling and lightly press down over the top to seal. Brush the top with egg wash. Your pastry sheet should now roughly measure 17.5 × 60 cm (7 × 23 1⁄2 in).

With a large kitchen knife, cut the pastry into vertical strips 2 cm (3⁄4 in) wide. This should yield up to thirty strips. Put the strips on lined trays and refrigerate for at least 30 minutes.

To create the twists, use your fingertips to gently stretch a strip of pastry, starting from the middle and teasing it out towards the ends. Pinch the ends and then rotate them in opposite directions to create lots of twists in the pastry. It should look like rope, about 30 cm (12 in) long. Repeat with all the strips, then return them to the trays and into the fridge to chill. At this stage, you can freeze them until needed.

To bake the straws, preheat the oven to 190°C (375°F). Line a large baking tray with baking paper (if baking them all at once, you’ll need two or three large trays). Put the twists on the lined tray, leaving a 4 cm (1 1⁄2 in) gap between each one, then sprinkle the remaining 40 g (1 1⁄2 oz) parmesan over the top.

Bake for 10 minutes, then reduce the oven to 180°C (360°F) and turn the tray. Bake for a further 5–6 minutes until golden and flaky. Transfer to a wire rack to cool for 10 minutes, then sprinkle with flaky sea salt. These are best eaten on the day they’re baked, but will keep for 2–3 days in an airtight container – refresh them in the oven at 160°C (320°F) for a few minutes.