Reposted from a wonderful poultry and homesteading blog: http://avianaquamiser.com/posts/Eating_the_whole_chicken/ 
If you’re like me, you learned to cook using chicken breasts, or perhaps the whole carcass if you were feeling adventuresome. Once you start growing your own broilers, though, you’ll probably feel the urge to eke every bit of goodness out of that animal’s body, both to honor the chicken’s life and to get more food for your work (and money.) Harvey Ussery’s The Small-Scale Poultry Flock  suggested eating more parts of the bird than I’d ever thought possible.
“Unborn eggs.” This is Ussery’s name for the yolks of various sizes you find inside adult hens. He harvests all of the yolks from pea size up and drops them into a bowl of hot broth. My mother-in-law, who grew up poor in the mountains of eastern Kentucky, knew exactly what I was talking about when I started telling her about these eggs — they were her favorite part of the bird.
Fat. Broilers are generally pretty lean, but if you cull an old hen, you’ll find a big deposit of fat on her belly. Previously, I’ve discarded this fat, but fat from pastured livestock is extremely good for you, so I’m changing my ways. Ussery recommends heating a cast iron frying pan on low, then adding small cubes of fat. Gently melt the fat until it has turned into a liquid with a few crinkly bits left behind. Strain out the cracklings (which you can eat as a snack or like croutons), then store the fat in the freezer for months, using it the way you would butter. I’ll have to wait until next year to try rendering chicken fat because I found a use for mine as soon as it came out of the bird — I pureed the fat in my food processor then mixed it in with some ground venison to turn the ultra-lean meat into delicious burgers.
Broth. Over the last year, I’ve come to feel that the broth I make from the carcasses and necks of my birds is the most wholesome and delicious part of the chicken. Harvey Ussery’s wife Ellen clearly takes broth seriously as well — she has an extensive recipe for broth in The Small-Scale Poultry Flock. Ellen Ussery recommends not only stewing up the carcass and neck, but also including the feet, hearts, gizzards, and heads.
Feet. Did you know that if you dunk the chicken’s feet just like you do the rest of the bird before plucking, it’s relatively easy to peel the scales off and leave clean feet behind? (This is tougher if you have a feather-footed breed like the cochin I experimented with, but is still quite feasible.) Feet make a great addition to the stock pot when you’re cooking down the rest of the bones to make broth.
Livers. I’m ashamed to say that I haven’t learned to cook livers in a way I find appealing yet. I plan to try Ussery’s recipe next year — saute the onions, then add the livers and cook until just rare; deglaze the pan with a little wine or sherry and serve. Recipe aside, I was glad to read that Ussery agrees with me about old livers — the fresh, red ones from young birds should be eaten, but when they turn yellow and pale, it’s best to discard the organ.
“Mountain oysters.” Ussery mentions that the testicles of mature roosters are also edible, but I don’t think he’s tried them himself.