I’m going to butt in here, hope that is allowed! Most chefs are creating the recipe from the very bottom up. A great writer has access to the same words the rest of the world does, they just put them together in a way that inspire people to consume their piece. We all have the same access a chef has to all of the same ingredients, the chef just puts them together better than others. Of course chefs use training and mentors to inspire their work, just as a photographer, painter, or actor, until their personal expression shows itself
I just re-read your comment. Are you asking about how a chef injects his own style when they MUST use someone else’s recipe?