The difference between pickles and this old-world technique of preserving foods (including fish, meat, and, here, vegetables) is that with escabèche, ingredients are cooked in a vinegar-based broth (called caldillo) to release their juices into the liquid, which tempers the sharpness of the brine.
This is so good. It's kind of a lot of sugar and I think you can reduce it a little. Just finished making it, cooling it down to begin the 24-hour chilling period but we could easily devour it all now. Will definitely make again and again.