Method

• 1.
  For the rough puff pastry, knead 150g butter and 60g our in a bowl until a dough forms. Roll out dough between 2 sheets of baking paper into a 2mm-thick rectangle. Transfer to a baking tray, cover with plastic wrap and chill for 1 hour.

• 2.
  Combine the remaining 50g butter and 140g flour in a bowl and knead to form a dough. Add vinegar, 1/4 cup (60ml) water and a pinch of salt and knead to combine.
• 3.
  Be careful not to overwork dough. Cover with plastic wrap and chill for 1 hour.
• 4.
  Place second dough piece on a lightly floured work surface and roll out into a 2mm-thick rectangle the same size as the rst rectangle. Place the first piece of dough on top of the second.
• 5.
  Fold one short end of pastry two-thirds of the way down the length. Fold the other end on top to enclose and form three layers. Enclose in plastic wrap and chill for 30 minutes.
• 6.
  Remove from fridge and place on a lightly floured surface with the layered seams facing you. Repeat rolling, folding and chilling method once more.
• 7.
  Meanwhile, heat the oil in a saucepan over medium heat. Add the onion and garlic, and cook, stirring occasionally, for 3-4 minutes until onion is translucent.
• 8.
  Add coriander and 2 1/2 tsp fennel seeds, and cook for a further 1 minute or until fragrant. Add the harissa and cook for 1-2 minutes. Spread onion mixture over a baking tray to cool.
• 9.
  Combine breadcrumbs and milk in a bowl and stand for 10 minutes or until absorbed. Add the lamb and onion mixture and season generously. Cover and chill until required.
• 10.
  Preheat oven to 200°C. Grease a large baking tray and line with baking paper. Place egg yolks and 1 tbs water in a small bowl and whisk to combine. Place pastry on a lightly floured work surface and roll into a 28cm x 40cm rectangle.
• 11.
  Halve pastry lengthways. Divide filling lengthways down the centre of each dough half. Brush edges with yolk mixture and roll to enclose, overlapping the seam slightly.
• 12.
  Halve each roll crossways and place, seam-side down, on the prepared tray. Score the top of the rolls, brush with remaining yolk mixture and sprinkle with 1 tsp sea salt and remaining 1/2 tsp fennel.
• 13.
  Bake for 30-35 minutes until pastry is golden and the lling is cooked through. Slice sausage rolls and serve with relish.