Using a mandoline slicer, cut the cucumbers, carrots, and mango into fine julienne strips.
For the cucumbers, slice only the outer part (the skin and firm flesh). Set aside the seeded center, as it releases water and can make the salad soggy.
Finely slice 3 leaves of iceberg lettuce into thin strips.
Separate the crab sticks (kani) into thin strands using your hands.
Place all the prepared vegetables and crab in a bowl and keep them refrigerated while you prepare the sauce.
In a separate bowl, combine all the sauce ingredients. Mix well until smooth and fully blended.
Pour the sauce over the salad mixture and toss gently until everything is evenly coated.
Sprinkle the crushed peanuts, roasted panko breadcrumbs, and roasted sesame seeds on top.
Give the salad a final gentle mix and serve immediately for the best texture and freshness.