Cut the ends off each cucumber.

Quarter each cucumber lengthwise and then cut each of these pieces in half horizontally (repeat the process once more if you prefer smaller pickles).

In a large bowl, combine the soy sauce, rice vinegar, sesame oil, brown sugar, salt, and red pepper flakes to taste, if using.

Whisk until the sugar is dissolved.

Add the cucumbers and stir gently until they are well coated. Sprinkle with sesame seeds.

Transfer to a covered container and refrigerate for at least 30 minutes but up to 2 days before serving.

Serve with other dishes or enjoy on their own as a crunchy snack.