Cut the ends off of 300 g Japanese or Persian cucumbers then rub the cut stems over the tops to draw out bitter white foam. Wipe it away, then sprinkle with coarse salt and roll them over the cutting board.
If your cucumber feels a little limp, soak it in ice water for 10-15 minutes to bring the firmness back.
Wash the salt off the cucumbers and pat them dry. Place one cucumber between two disposable chopsticks or similar. Hold the knife at a 45° angle and make fine slices every 2-3mm.
Flip the cucumber horizontally and repeat the cuts in the same direction (this will make the cuts parallel to the cuts on the other side). Cut the cucumbers into halves or thirds.
Pour 500 ml water into a large bowl and stir in 1 tbsp salt until fully dissolved. Place the cucumber in the salted water and soak for 10-20 minutes.
While you wait, grab a bowl and add 2 tbsp yellow miso paste (awase), 1 tbsp honey, 1 tsp Japanese soy sauce (koikuchi shoyu), 1 tsp chili bean sauce (toban djan), and ¼ tsp Chinese-style chicken bouillon powder. Mix until smooth, then crush 2 g bonito flakes (katsuobushi) and sprinkle it into the bowl. Add ½ tsp grated ginger root and mix once more.
Drain the cucumbers and squeeze gently, removing as much brine as possible without breaking them. Place the cucumbers in the bowl with marinade and carefully spread it over the surface and between the cuts.
Arrange the coated cucumbers in a sealable bag, or container with plastic wrap/parchment placed directly on top. Refrigerate for at least 1 hour, up to 24 hours.
Right before serving, combine 1 tbsp toasted sesame oil, 1 tbsp ground sesame seeds, ½ tsp grated garlic, ½ tsp grated ginger root, ½ tbsp unseasoned rice vinegar (komezu), and 1 tsp chili flakes in a bowl to make marinade B. Pour the accumulated water out of the cucumbers and add marinade B, and gently toss to coat.
Plate up with a sprinkle or 1 tsp toasted white sesame seeds or 1 tbsp finely chopped green onions. I recommend enjoying this dish over hot rice.
Notes
Do not skip the salt brine: Cucumber holds so much water that without draining it the marinade turns watery and pools by the next day. Soak 10 to 20 minutes, then squeeze gently once it bends. This decides the result.Do not over-cut the accordion: Cut too deep and the scores from both faces overlap and the accordion tears apart. Lay chopsticks along each side and stop the blade at 80 percent depth. Little debris in the brine means you cut it well.Adjust for your miso's saltiness: Salt levels swing a lot by brand and type. Even with awase miso, if yours is on the salty side, cut the amount slightly in Marinade A so the dish does not turn too salty.