The day before, immerse the salted cod in cold water.
In a saucepan, poach the salted cod in milk with garlic and an onion stuck with cloves, for 5 to 10 minutes to simmer. Strain the salted cod and remove the bones and skin.
In a blender, shred the salted cod until it becomes a kind of dough. Drain this dough in a sieve. In a blender bowl, put the salted cod, cottage cheese, cream and blend. Adjust seasoning and refrigerate.
In a steam cooker, arrange the washed leeks and add the fresh cod on top. Sprinkle with sesame oil and cook for 10 minutes. Arrange on the plate the cold salted cod cream, and then add the leeks and the fresh cod.