Contract, yes. Book, not yet. A Question

The other night a fellow author and friend told me she was using the NaNoWriMo to finish a novel she owed her publisher. Said novel was already contracted and due to her editor before the end of November.

There are publishers out there who actually CONTRACT a book before it's written? Yes, hers is part of a series, but when I was working on book three of the Thunder trilogy, I knew I needed to have it in by a certain time so that the edits/cover/etc. could be done in a reasonable and timely fashion, but it had NOT be contracted. Not until it was finished.

How is it possible for one to "pitch an idea" to a pub for an unwritten book/story/idea/plot, and get a CONTRACT?