Making fish pie today so plenty of grisly remains, in particular, prawn heads, which are The Best Thing Ever for making fish stock. I had twelve “large” prawns which weighed around 350g in total. (Yes, I know, in certain parts of the world, these would be considered tiny, but hey ho.)
So, heads cut off, shells removed, and into a medium saucepan. The meat was butterflied (use a small pair of scissors to do this) to remove the vein (well, the gastrointestinal tract) and reserved for the fish pie.
Meanwhile, the grisly remains were given a good rinse, and I added: half an onion, salt, a few black peppercorns, and a bay leaf. Oh, and since I was skinning a cod fillet, I threw the skin in as well. (I was also skinning a smoked haddock fillet, but didn’t use that skin as the stock would have tasted of nothing but smoked haddock. The salmon skin was too oily, so also discarded.)
Topped up with cold water to 2L, and the whole lot brought to a gentle simmer for twenty minutes, and then strained through a fine sieve.
The resulting liquid was allowed to settle, disgorging quite a large amount of sediment.
The saucepan was given a perfunctory rinse, and the liquid carefully poured back, so the sediment stayed in the bowl. Finally, brought back to the boil briefly, and the small amount of scum skimmed off. Final yield: one litre of fishy goodness.