Rinse your cucumber under cold water and peel, cut lengthwise and remove the seeds. To easily remove the seeds, you can use a spoon to scrape out the seeds gently.
Clean and slice the onion very thin, you will use about half of a small onion. Also, if you have fresh green stems on your white onion, cut some of those as well.
Slice the cucumber one half at a time in about 1/4 inch slices, so these are not thin slices.
Add all ingredients of the sauce in a bowl and mix. Give a taste to make sure it has the best heat and salt for your flavor profile.
Add your cucumbers and onions to the serving dish, add the sauce and mix well. Refrigerate for at least 30 minutes. This give time for the salad to absorb the wonderful sauce to enhance the flavor and chill the cucumbers for a more refreshing salad.
Garnish with fresh chopped parsley and another pinch of crushed red pepper if you like the additional heat.