I could see LLMs being helpful to explore what's out there, like finding similar dishes or dishes involving a specific set of ingredients or dishes involving a particular technique, but a pretty poor tool for the actual technicalities of cooking or more importantly the uniquely personal aspects of food culture.
I dunno. I'd just buy larousse and on food and cooking.
Food lab, for example, covers buying storing and cooking lamb + a guide for a 5-7lb boneless leg across 5 or so pages. Kenji goes through great lengths to build intuition. I'm sure larousse, which is more of an encyclopedia, covers lamb quite extensively but it's probably more terse.
The internet can be an excellent source, but like most things it depends on who is writing it down.