Start by slicing the English cucumber evenly into thin uniform slices. Toss them in a large bowl with really cold water to keep them crisp.
Add the cucumber slices to a large mason jar along with the salt. Place the lid on and allow it to sit for a few minutes, then pour out any excess liquid.
Add in the soy sauce, rice wine vinegar, toasted sesame oil, minced garlic, chili oil, green onions, and red pepper flakes.
Seal with the lid, and shake well to coat everything evenly.
Top with sesame seeds and enjoy!
Notes
For the best results, refrigerate the jar for at least 10 minutes before serving. The cold temperature helps the flavors meld together beautifully.A mandoline slicer is not needed, simply cut the cucumber into thin, uniform rounds.