Austerlitz
I can count on one hand the number of books I've read in the past decade that immediately overwhelmed me with how obviously and singularly great they were, not just in deployment of prose and style or in narrative structure or in content and message but how all of these things swirled together in a perfect cocktail, each informing and enhancing the other — indeed, this sort of gestalt analysis of a piece of art seems more obvious to me in the context of video games (see my writing on celeste), where it's easier for me to separate the act of "playing the game" from the act of "internalizing/critiquing the game."
But Austerlitz, like Pale Fire or To the Lighthouse (to call out two examples that come most readily to mind), as a perfect gem — unique, brilliant prose supporting a terrific and (to flirt with redundancy) unique post-modernistic struture, neither of which are rococo but in fact are deployed specifically to tell the story that Sebald wishes to tell.
A jewel of a book; everyone should experience it.