Since the late 1800s, when the Chinese began immigrating to Japan, many Chinese words have been adopted into the ramen lexicon. Chintan is the word we ramen-making folks use to describe a clear soup, no matter what type of bone it is made with. The most common is a tori chintan, or chicken soup. If this is the point where you say to yourself, Oh yeah, I know how to make chicken stock, I’ll just skip ahead, stop yourself and keep reading. I have taught dozens of French-trained chefs how to make this stock, and the response is always the same: “I had no idea.” I will dare to say that you have most likely been making burned chicken stock your whole life and you never knew.
Timing-wise, ideally you want to start the chintan in the morning so you can have time to make paitan on the same day, but you can hold the bones overnight in the fridge and start the paitan the following day, if necessary.