Place dried wakame (and any other dried seaweed like tosaka or arame) in a large bowl. Cover with cold water and let soak 8–10 minutes until rehydrated and tender. If using thicker dried varieties, warm water for 4–6 minutes can speed rehydration—do not over-soak.

Drain the seaweed well in a sieve, pressing gently to remove excess water. Chop larger pieces into bite-size lengths (about 1–2 inches). Transfer to a mixing bowl and set aside.

Aromatics & Vegetables

While seaweed soaks, prepare vegetables: thinly slice green onions, julienne cucumber and carrot if using. Place them in a small bowl and pat dry to remove excess moisture so dressing adheres better.

Dressing

Make the dressing

In a small bowl or jar combine rice vinegar, soy sauce, sesame oil, mirin, sugar, and lemon juice. Whisk or shake until sugar dissolves and the dressing is homogeneous. Taste and adjust balance: add a little more sugar for sweetness, more soy for salt, or more vinegar for brightness.

Stir in toasted sesame seeds and red pepper flakes to the dressing.

Assemble & Finish

Add the drained seaweed to the bowl with prepared vegetables. Pour the dressing over the seaweed and vegetables. Toss gently but thoroughly so dressing coats everything evenly. Let sit 5–10 minutes to allow flavors to marry; toss once more before serving.

Toast a nori sheet lightly over a gas flame or in a dry skillet until crisp but not burned; let cool, then slice into thin strips and sprinkle over the salad along with the remaining toasted sesame seeds. Garnish with cilantro or mitsuba if using.

Taste and adjust seasoning — add a pinch of salt or a splash more soy sauce if needed. Serve chilled or at cool room temperature.