In a large shallow bowl, combine the cucumber slices and salt. Cover and refrigerate for 60-90 minutes
Move cucumber slices to a colander and wash well, making sure all the salt is rinsed off
Return to the bowl and toss in the onions
In a medium saucepan, combine the remaining ingredients and heat until just simmering and all of the sugar is dissolved, stirring occasionally
Pour the hot vinegar mixture over the cucumbers and let cool for about an hour
Cover and store in the refrigerator overnight
Notes
Store pickles, covered in juice, in an airtight container in the refrigerator for up to 3 monthsIf you like sweet and spicy, add a whole chili or chili flakes, to the final mixture, to taste