Trim ends off cucumbers and cut each in half long ways once, then cut each of the halves in half longways once more. Slice into 1/4 inch pieces. Toss with salt and sweat cucumbers by sitting in a colander for 20 minutes.
While cucumbers are sitting, whisk all dressing ingredients together and set aside.
Drain cucumbers and rinse. Pat dry using paper or kitchen towels.
Toss cucumber, carrot, and red onion in dressing. Add peanuts and serve right away.