What is the origin of the idiom "the fat hit the fire" and when to use it?

The idiom "the fat hit the fire" is an expression used to describe a situation where a problem or conflict intensifies or becomes more serious. It conveys the idea that a previously manageable or contained issue has now escalated and reached a critical point. The origin of this idiom can be traced back to the imagery of fat dripping onto a fire, which causes a sudden burst of flames and increased intensity.