Method

• 1.
  For the creamy dressing, place all ingredients in a small bowl and use a fork to whisk together until well combined and smooth. Season well. Set aside at room temperature.
• 2.
  Cook potatoes in a large saucepan of boiling water over high heat for 10-12 minutes or until just tender when pierced with a skewer. Drain well, then transfer to a large heatproof bowl and cool to room temperature.
• 3.
  Meanwhile, heat a large non-stick frypan over medium heat and cook speck, turning occasionally, for 10-12 minutes or until all fat renders and speck is crisp and golden. Use a slotted spoon to transfer to paper towels to drain, reserving fat in pan. Set speck aside to cool to room temperature.
• 4.
  Reheat same pan, with reserved rendered fat, over medium-high heat. Cook sourdough crumbs, tossing constantly, for 1-2 minutes or until crisp and light golden all over. Remove pan from heat, season crumbs well and cool to room temperature before storing in an airtight container in a cool, dark place overnight.
• 5.
  Once potatoes have cooled, add creamy dressing and parsley stems, then toss gently to combine and coat well. Season well. Spoon into the base of a 4L (16 cup) capacity glass pedestal serving bowl. Sprinkle with speck, then top with egg.
• 6.
  Toss onion, lettuce, dill and parsley leaves together in a large bowl, then pile on top of egg in bowl. Cover and chill for at least 6 hours (overnight is best to allow potato salad flavours to develop).
• 7.
  The next day, remove salad from fridge and sprinkle with crumbs. Serve.