Quoted from an email:
It’s vinegar and brown sugar, equal amounts, somewhere between half a cup to a cup, a bay leaf, raisins, and a sliced onion.
We usually make this from frozen fish so what to do if it’s fresh were not sure.
Three-four slices my mom usually microwaves it, with enough water that the fish is half-covered: five to seven minutes to defrost on low, then eight to twelve minutes on high, turn it over at some point.
For more than 3-4 slices, you should cook it in a pot.
Should be tightly covered (microwave or pot)
Basically you can tell that it’s ready when it doesn’t look raw anymore.