Method

• 1.
  For the leek and spring onion oil, place all the ingredients in a blender and whiz on high speed for 10 minutes or until a bright green colour.
• 2.
  Line a colander with a piece of muslin or clean Chux cloth large enough to hang over the sides and place colander over a bowl. Place the leek and spring onion mixture in the colander and leave overnight to drain. Freeze oil in small containers if not to be used within 3 days.
• 3.
  For the soured cream, place the cream in a saucepan over high heat up to 38°C.
• 4.
  Add yoghurt and stir to combine. Pour mixture into a jar, seal and place in a warm spot for 8-12 hours. Soured cream can be stored in the fridge for up to 1 week.
• 5.
  Heat a charcoal grill over medium- high heat. Add leeks and cook for 40-45 minutes until blackened and starting to soften. While hot, place leeks in a container, pour over the vinegar, seal tight and leave in a warm spot for about 20 minutes. Place spring onions on the grill and cook for 8-10 minutes until starting to char and soften. Add to the container with the leeks and allow to rest for 2 minutes.
• 6.
  Season with salt.
• 7.
  To serve, mix vinegar from the leek and spring onion mixture with the strained onion oil. Place 2 tbs of the oil and vinegar on a serving plate then add 2 tbs soured cream. Slice leeks in half and arrange on top with the spring onions.
• 8.
  Serve.