Wash thoroughly, then cook the leek in a steamer or in boiling salted water until the tip of the knife easily penetrates the vegetable. Cool.
Add three tablespoons of good olive oil, one tablespoon of red wine vinegar, one teaspoon of mustard, salt and pepper.
For one egg pocket of smoked cod:
Soak three slices of bread in milk. Mix the mixture with the juice of half a lemon and 6cl of olive oil.
Mix 100g of breadcrumbs with 35g of grated parmesan and a heaping tablespoon of Meaux mustard. Add a dash of oil. Cook for about 7 minutes at 180 degrees.
Make an oil of leek greens by mixing in a blender leek greens and sunflower oil.
Assemble the mayonnaise by adding an egg yolk, a spoonful of mustard and the leek oil.
Place the vinegar-coated leek in the center of the plate, with a quenelle of tarama on top.
Add the mustard crumble, and around it, add a few dots of mayonnaise.