The phrase “like water for chocolate” comes from the Spanish como agua para chocolate.
This phrase is a common expression in Spanish speaking countries and was the inspiration for Laura Esquivel’s novel title (the name has a double-meaning).
In some Latin American countries, such as Mexico, Hot Chocolate can be made not with milk, but with water instead. Water is boiled and chunks of milk chocolate are dropped in to melt thus creating the hot chocolate. The saying “like water for chocolate,” alludes to this fact and also to the common use of the expression as a simile for describing a state of passion or – sometimes – sexual arousal. In some parts of Latin America, the saying is also equivalent to being “boiling mad” in anger.
The phrase is also commonly used to mean something is “perfect” for something else.