Final answer:
To safely cool a large pot of soup, the food worker should use an ice water bath to rapidly reduce the temperature of the soup, thus avoiding the multiplication of harmful bacteria.
Step-by-step explanation:
The correct way to cool a large pot of soup is by using an ice water bath before transferring it to the refrigerator. This method rapidly reduces the temperature of the soup, preventing the growth of harmful bacteria that could lead to foodborne diseases.
The process involves placing the pot in a sink or large container filled with ice and water and stirring the soup to ensure even cooling. This technique is preferred because it quickly lowers the temperature of the soup, taking it through the temperature danger zone (between 135°F and 41°F) where pathogens multiply most rapidly, in a faster way than simply leaving the pot at room temperature or placing it in the refrigerator without pre-cooling.