Slice the Cucumbers: Cut the Persian cucumbers into rounds approximately 1/4 inch (6 mm) thick. Keeping the slices as even as possible ensures they soften and absorb the dressing at the same rate, resulting in a uniform texture throughout the salad.

Salt the Cucumbers: Place the sliced cucumbers in a large colander set over a bowl or sink. Sprinkle with the salt and toss thoroughly. Let them stand for 20 minutes. During this time, moisture will begin collecting beneath the colander, which is essential for preventing a watery salad.

Make the Dressing: While the cucumbers drain, whisk together the rice vinegar, soy sauce, toasted sesame oil, sugar, garlic, chili crisp, and optional red pepper flakes in a small bowl. Continue whisking until most of the sugar dissolves, creating a well-balanced dressing that will enhance the cucumbers.

Dry the Cucumbers: Shake the colander well to remove the released liquid. Spread the cucumbers on a clean kitchen towel or several layers of paper towels and blot gently. They should feel cool and slightly flexible but not wet, which is crucial for achieving the right texture in the final dish.

Dress the Salad: Transfer the dried cucumbers to a large mixing bowl. Pour the dressing over them and toss until every slice looks lightly coated. This step is important for ensuring that the flavors are evenly distributed throughout the salad.

Add the Finishing Ingredients: Add the sliced green onions, toasted sesame seeds, and cilantro, if using. Toss gently so the onions and sesame seeds are distributed without breaking the cucumber slices. This adds both flavor and visual appeal to the dish.

Rest Briefly: Let the salad stand for 5 minutes before serving. This gives the cucumbers time to absorb some of the dressing while remaining crisp, enhancing the overall flavor of the salad.

Taste and Serve: Toss the salad once more and taste it. If it seems too sharp, add a small pinch of sugar. If it needs more acidity, add a teaspoon of rice vinegar. Serve chilled or at cool room temperature for the best experience.