Coarsely chop deseeded cucumbers into rough one-inch planks on the bias. For dramatic flair and to maximize seasoning absorption, place whole cucumbers on a cutting board and whack lightly with a rolling pin, breaking the flesh open slightly before deseeding and chopping into irregular, bite-size pieces.
In a large bowl, toss chopped cucumber with salt, massaging gently with hands. Drain over a sieve for 10 minutes.
Meanwhile, toast sesame seeds in a small dry skillet over medium-high heat for 2–3 minutes until golden and fragrant. In a small bowl, whisk soy sauce, sesame oil and vinegar.
Squeeze cucumbers gently with hands to remove excess water and return to bowl. Toss with dressing.
Taste and adjust seasonings to preference, adding small amounts of grated ginger, garlic paste or chili flakes if desired. Chill for at least 30 minutes.
To serve, chop shiso leaves in a fine julienne or coarsely chop cilantro. Garnish cucumbers with sesame seeds and a flurry of herbs. Serve immediately while cold. Serves 4–6 as a side dish.