The origin of the word escabeche is Persian, and was brought to Spain by the Arabs during the Moorish conquests. The word derives from al-sikbaj, the name of a popular meat dish cooked in a sweet and sour sauce, usually vinegar and honey or date molasses.
Its usage seems to have been increasing since the 80's/90's mainly in Australia. Its origin is not clear, probably from 'crash' in the sense of 'extreme'.
(slang, Australia, New Zealand) Very good, excellent; very well.
Well well well, don′t you look crash hot in your new sunnies!
I'm sorry boss, I can′t come in to work today, I′m not feeling too crash hot.
1991, Antonio Casella, The Sensualist, page 28,
Certainly Nick isn′t too crash hot on the old pen, something which he admits freely.
Perhaps a nonstandard adverbial usage of crash (“extremely”) + hot (“performing well”).
The following extract refers to crash hot as a mid-80s Australian expression:
I was young and living in Australia with muscles that worked. My time in Sydney wasn’t all wasted, though: I did buy a pair of Hot Tuna boardshorts – they were crash-hot (authentic mid-80s Aussie slang).
Best Answer
Escabeche is from Persian al-sikbaj
The LA Times blog Forklore: The roots of escabeche:
This one makes for a good read.
And then, Ichthyology thinks: