in england , the idea of a bag of frozen fish in parsley sauce that you could reheat to an edible standard by boiling it in a saucepan of water was known to only a few and remained an experimental procedure , and when it came to it , an extremely hazardous activity as you held the scalding hot bag in one hand while you wielded a pair of scissors with the other , trying all the while to cut the corner off the floppy plastic sack and release the lava flow of boiling piscine liquid somewhere in the direction of the plate .