You should be frugal when it comes to cooking, utilizing whole chickens to full measure. The Ziploc freezer bag in the bottom slot of my freezer door houses little packages of chicken fat that I’ve trimmed from whole chickens – to be used in other dishes by and by.
Passover is one holiday that sees me pulling chicken fat out of deep-freeze, namely for matzoh balls and chopped liver. I also use it to roast potatoes and other root vegetables, either adding a bit to my usual canola oil, or going for the gusto and using 100% rendered chicken fat for a special occasion. Given the saturated fat content of chicken fat versus that of duck fat, I tend to use the former when being luxurious, though I like having both on hand.
Rendering chicken fat for use is easy, and you can do it one of two ways:
1) After you defrost it, cut it up and spread it out in a saute pan over a low flame. As it renders, spoon into a container. When cool, cover very well and store in the refrigerator.
2) Place chicken fat in a saucepan and barely cover with water. Simmer over low flame, uncovered. When it starts to sizzle, almost all the water will have evaporated and you can spoon the rendered fat into a container. If you find you have too much water, just put the cooled, covered, container in the refrigerator and then pry off the chicken fat when it is solid and move it to a fresh storage container.
You should also be saving chicken carcasses for use in congee and stock. Stay tuned.