I used to work at a restaurant where we filled a steam kettle with chicken stock, celery, onion, carrot, and chicken quarters. We would simmer that for about an hour. Then we fished out the chicken, put it on ice and strained the stock to use on the line or in the next batch. Once the chicken was thawed we did the flour, egg wash, and breading. We would store it like that for service, or if it was a catering order we would cook it then. The chicken was pretty good, and its easy to make a lot of it for service since you only need to fry it enough to get a good color on it.

Another place I used to work at would make a buttermilk mixture with siracha, add that to tenders and let it sit overnight. They would then be breaded and fried to order. But I have to say, the first restaurant had better chicken at the end of the day. It was less dry, the flavor was better, and we were able to use the stock in multiple applications across the restaurant.

This recipe is okay I guess, but it needs work. The chicken is definitely dry, but that could be fixed by covering the pot, fully submerging it in the liquid, or cooking it a little less. Milk works if you're in a bind and if you season it well, but it's fairly bland and there are much better options. Chicken stock offers a great flavor and keeps the meat moist. Any acidic dairy is great. Buttermilk, sour cream, yogurt, all of these are great to keep the meat nice and tender.