Well I've been unemployed for a month and being a worthless man, cooking and eating. Have several pints of various soups in my cabinet at the moment. I taught myself sanmai oroshi and cleaned two mackerel--the second was perfect, first was okay but a learning experience. Used the bones and tail for a fish stock (だし dashi), cleaned and segmented the heads for fish head soup. Also did a black bean soup.
Also did chicken at 135F (you have to keep it there for half an hour; it's not done the moment you read 135 on the thermometer), which was fantastic--I highly recommend this if you can maintain the internal temperature of the chicken (I did so by opening and closing the oven door and checking every 8-10 minutes with a meat thermometer). Ate that with stuffing--stale bread seasoned and cooked with chicken stock--and steamed sweet potatoes that I ran through the food mill's medium sieve (I should add butter next time).
So after the chicken and the black bean soup, I had a frozen carcass (and neck/gizzard ... ate the liver and heart), wings, a frozen onion from before, more fresh onion bits, a bunch of leek garbage (tough leaves and such, parts you don't use) and excess leek, celery I wasn't going to eat, some carrot. Obviously, made chicken stock. Lessons learned: 8qt stock pot sucks, get the 12qt one. Stainless steel, Wegman's.
But wait, there's more! </Billy Mays>
I threw that carcass into the stock pot wholesale, with all those vegetables, a handful of black pepper corns, and a bay leaf. So far so good, except i didn't trim the fat off the carcass at all.
You all know how to make stock. Bring the temperature up, simmer it--don't boil. Keep it there for a couple hours. Strain that out, have liquid. So far so good.
The liquid is full of fat. You have to let it sit and cool for a few minutes to a few hours for that to rise out--refrigeration can cause problems or it can work fantastically, but putting a big hot pot in your refrigerator may not be the best idea. Plus that much thermal mass bring so much heat that the refrigerator serves to prevent it from cooling by creating a restricted insulated space. Let that cool on the counter for a bit, then refrigerate.
If you're so inclined, you can pour the stock into a 4 cup Oxo Good Grips fat separator, let it separate in batches for maybe 10-20 minutes, then pour it off the fat. This is a good way to separate hot. If you want to separate cold, you can just let it cool and then chill it over night, removing the solid fat the next day.
In either case, keep the fat. It's called schmaltz, you can fry things in it, it's excellent. Try baking diced (to about 2 inch diameter) peeled potatoes in it, they'll absorb the fat. If you're so inclined, you could use the fat separator and pour the fat into a tall container to quickly hot-separate it and then more easily purify it by cooling in the refrigerator. In any case, once you've retrieved the fat by any method, you should let it separate and then chill it. If you've got it in a tall container, take the top part, it's all pure. For the remaining bottom layer, wash the chilled fat in chilled ice water to remove the stock and retrieve the fat.
If the stock is not strong enough, use it as the base water and find another chicken. Make another stock (double stock). Don't boil the stock to reduce.
If you want to do another day of work, go ahead and separate out an egg. Mix the egg white into the cooled stock, stir it, and add the crushed egg shell. Bake and eat the yolk. Bring the stock to a simmer, then strain it through a steel mesh strainer and cheese cloth. The egg white will bind to any bits of bone or other cloudy stuff; heat of course solidifies it, and then you remove the egg white by straining and get an ultra clarified stock.
At this point, pour the hot stock into jars, process for 15 minutes (20 for quart jars) at 11 pounds. If you wish, the schmaltz can go into 4oz jars, process for 15 minutes at 11 pounds as well.
Compost the remaining vegetables and chicken parts. Use them to grow porcini.
Packaging recycled: 100%
Waste food composted: 90%
Waste food recycled: 10% (the bread, into stuffing)
Total trash generated: 0
The fish organs ... can be prepared. I don't know the traditional recipes and methods, so have no culinary experience to follow from. You can compost these, but it is a waste.