[Request processing failed; nested exception is org.springframework.http.converter.HttpMessageNotWritableException: Could not write JSON: Infinite recursion (StackOverflowError)...
I had to do some poking around and reading up on documentation to figure out how to fix it.
As it turned out, the fix wasn't that complex and the culprit was Jackson: the Java-JSON processor being used to transform the retrieved Java entity to a JSON representation.
The error occurs when you try to retrieve an entity that has a bi-directional @OneToMany relationship with another entity.