The author of a literary work gets a copyright, but the author of a
gourmet dish or a brick wall does not.

Wrong. Both can be copyrighted and at least gourmet dishes have been
copyrighted. Presumably one could get a copyright on the design of a
brick wall if it was sufficently unique.

I don't want to get into chapter and verse on this detail, but my study of
the law (which you seem to hold in contempt, while holding your own
background as far above mine) finds an entirely different conclusion than
yours. If you'd care to cite a single instance of copyright for a recipe
or a bricklaying pattern, that is, that prevents anyone from making copies
by making that dish or building that wall, then I'd be thoroughly
impressed.