2 1/4    Parts vinegar
2    Parts salt

Filet out the he middle portion from back to front. Marinate for one day in
a mixture of salt and 5% vinegar until the surface of the fish is “cooked”
(like seviche). Freeze overnight and then slice thin and serve. I didnt
get the proportions of salt and vinegar but I am assuming that it is very
similar to what I use for pickling fish.