Comment by rybosome

Others have pointed it out, but it’s the juxtaposition of the fact that she’s definitely not an expert in this subject with a lesson in the subject.

There’s some subtle bits to the humor depending on how charitable you’re feeling. It might just be absurdist, as in “Blackbeard’s guide to astrobiology”, or it may be more mean spirited and playing on a belief that she is not intelligent.

TL;DR - the joke formula is just:

subject=…

person_not_familiar_with_subject=…

joke=“${person_not_familiar_with_subject}’s guide to {subject}“

And the amount of implied cruelty in the comparison is variable.