That's a tough one because 'chaos magic' isn't a specific, well-known title like 'The Name of the Wind'. It sounds like you might be referring to a book about chaos magic as a practice, or perhaps a novel where chaos magic is a central theme. Without an exact author or title, I can only guess. There's 'Liber Null & Psychonaut' by Peter J. Carroll, which is a foundational text on chaos magic itself—its main 'plot' is more of a manual, outlining techniques and philosophy for reshaping reality through belief. Then there's fiction like 'The Invisibles' by Grant Morrison, which weaves chaos magic into a comic book narrative about rebellion against cosmic control. Could you mean something like that?
If you're thinking of a fantasy novel, I remember 'A Darker Shade of Magic' by V.E. Schwab uses a system of elemental magic, but not chaos magic per se. Maybe you're blending concepts? The core idea in most chaos magic texts is that belief is a tool, not a truth, and the practitioner uses sigils, rituals, and paradigm shifts to achieve results. The 'plot' is essentially the reader's own journey into applying those ideas. It's less a story and more a set of instructions for personal experimentation.