Place the dried wakame into a heatproof bowl and pour 250 ml warm water over it. Let soak 8–10 minutes, until fully rehydrated and softened. The wakame will expand several times. Drain in a colander and gently squeeze out excess water. Chop into bite-sized pieces if large.

Prepare vegetables

While the wakame soaks, thinly slice the cucumber and shred the carrot. If cucumber is watery, lightly salt (a pinch) and let sit 5 minutes, then blot with a paper towel to remove excess moisture before adding to the salad.

Dressing

Mix dressing

In a small bowl or jar combine 3 tbs rice vinegar, 2 tbs soy sauce, 1 tsp toasted sesame oil, 1 tsp sugar, 1 tsp mirin (if using), 1 tbs fresh lime juice, 1/2 tsp grated fresh ginger and 1/2 tsp minced garlic. Whisk or shake vigorously until sugar dissolves and ingredients emulsify.

Taste and adjust

Taste the dressing and adjust balance: add up to 1/2 tbs more rice vinegar if you want brighter acidity, more soy for saltiness, or a pinch more sugar to round flavors. Note: sesame oil is strong — add gradually.

Assemble & Finish

Combine salad

In a medium bowl place the drained wakame, sliced cucumber and shredded carrot. Pour the dressing over the salad and toss gently but thoroughly so all components are coated.

Season and rest

Sprinkle 1 tbs toasted sesame seeds, 1 tsp toasted nori strips or 1 tsp furikake (if using), 1 tbsp thinly sliced scallions and 1/4 tsp red pepper flakes over the salad. Toss once more. Let the salad marinate at room temperature for 10–15 minutes to allow flavors to meld. Taste and add salt or a splash more soy sauce if needed.

Serve

Transfer to a serving bowl and garnish with a final pinch of sesame seeds and scallions. Serve chilled or at room temperature. Leftovers keep tightly covered in the refrigerator for up to 2 days; stir before serving as liquid may settle.