Remove the dark green part from the leek. Cut stems into pieces about 7 cm long. Cook in salt water for a few minutes until soft.
Sprinkle avocado with juice of one lemon. Divide anchovies, leek, avocado and olives evenly on plates.
For the salad dressing, finely chop shallot, coarsely chop peterli. Mix with vinegar and oil, season. Drizzle sauce over the arranged ingredients.