Looking for recommendations for how-to-write-essays books

I’d like to get a little into writing prose, specifically essays - not the academic type that is required as a deliverable in tertiary education (I’ve written my fair share of those), but rather the lengthier, more literary essays in which you elaborate in depth upon a thought or idea. Does anyone here have recommendations for books with helpful advice on how to make them more effective? When I google for how-to-write-essays books, I get plenty of material targeting college students, but not really what I am after.

I think William Zinsser’s On Writing Well is pretty much the gold standard of non-fiction writing. I think you would be happy if reading it made you as good a writer as its author.