For our purposes, I have taken a slightly different approach to preparing it. After you have a made a batch of stock and allowed it to cool for a day or two, a layer of fat that was cooked off of the birds will form on the surface of the stock. After it has fully solidified, it can be removed, either by skimming it off if it is on the watery side or cut with a knife and removed by hand. If you make frequent batches of stock you can hold onto this until you have enough to make a larger batch of schmaltz, but no more than a week.
Put your fat into a heavy sauce pan and let it heat up on a low heat. After it melts and starts to get hot, the water and stock that was still on the fat will begin to cook off. You will hear it rumbling and sizzling under the fat as it cooks off. When the noise has stopped you are pretty much done. Any remaining solids that were in the fat will have cooked and settled on the bottom of the pan. After the fat has cooled down to room temperature (or pretty close to it), it can be ladled off and put into a clean mason jar. It should be stored in the refrigerator.
So now that you have a fresh batch of schmaltz made, what do you do with it? I use it to cook with. For my home, I always looked as this as free fat. I cooked the bones and trimmings for the stock and anything extra after the stock is a bonus. When sauteing, I use this in place of any other oil. It has a higher smoke point and it is healthier than any of the vegetable fats normally used. I have also used this in pie crusts, especially when making pot pies or any savory crusts or dumplings. The added taste from the chicken fat will greatly increase the flavor of your overall dish. I also use this to saute vegetables, which adds even more flavor to them. This is also a great oil for stir frying with. Again the high smoke point makes it great for the high temperatures of a stir fry.
So if you are keeping track of savings, you buy a whole chicken at the store. If you bone out the meat, you can get a meal or two of of this meat alone. The bones go to make chicken stock that can be used in other dishes. Any meat that was still on the bones can be picked off and used for another dish, like a cassarole, or given to the dogs, which they will love you for. The fat from the stock can be rendered and made into schmaltz, which you use to cook with. How is that for stretching your money?
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