Cover and soak 1 Tbsp dried wakame seaweed in water until it softens and hydrates, about 5 minutes.
Grind 3 Tbsp toasted white sesame seeds in a pestle and mortar (Japanese-style wooden pestle and grooved mortar), keeping some seeds unground for some texture.
Add 2 tsp sugar, 1 Tbsp soy sauce, and 3 Tbsp rice vinegar (unseasoned) and mix well. Set aside.
For 1 American cucumber, I usually like to make a striped pattern by alternately peeling a ½-inch-wide strip lengthwise, then leaving a strip of the skin intact. With this method, the cucumber slices have some decorative dark green accents and a little bit of extra crunchiness.
Center-align the cucumber on the spiralizer and press firmly to secure both ends (for the Inspiralizer, set to “Blade A“ for wide ribbons). If you don‘t use a spiralizer, simply cut the cucumber into thin slices with a knife.
Spin the handle clockwise to spiralize. Using a kitchen shears or knife, cut the spiralized cucumber into shorter lengths.
Sprinkle ¼ tsp Diamond Crystal kosher salt on top and rub it into the cucumber. Set aside for a few minutes.
Squeeze the excess moisture from the cucumber and place in a bowl. Squeeze the excess moisture from the wakame and add to the bowl.
Before serving, pour the sesame dressing over the cucumber and wakame, and mix well together. Divide into individual dishes or place in a large serving bowl. Serve immediately.
To Store
I don’t recommend keeping it for a long time as moisture from the cucumber will dilute the dressing and the salad will become slightly pickled. If that’s okay, keep it in an airtight container and store it in the refrigerator for up to 2–3 days.