We do not have a limitless supply of ice in our home kitchen to cool down pots of sauces and not-stocks. When we need large quantities of ice we have to run to our corner store and buy a bag or three. What we do have on hand is a dewar of liquid nitrogen. Last evening we tested liquid nitrogen's cooling ability on a batch of Bolognese sauce. (Chef's have to eat.)
It should not have been a giant leap to use the nitrogen as a functional cooling tool. When we deliberately tried liquid nitrogen cooling for the first time and were able to take extremely hot sauce to temperatures under four degrees Celsius in five minutes, a new benchmark in efficiency and safety became apparent. While liquid nitrogen cooling may not be the most cost effective method, it is certainly the most time efficient technique that we have come across.
*The liquid nitrogen that we stirred into the sauce to cool it down evaporated completely out of our mixture. There are no toxicity issues with this technique and no reason to be afraid to use it.