Deceit, Desire, and the Novel is where René Girard first laid out his mimetic theory: we don’t really know what we want, so we learn to desire things by imitating what others desire. He builds the idea by reading Cervantes, Stendhal, Flaubert, Proust, and Dostoevsky, which makes this an interesting place to start, as I have only read some of these authors.
There are a lot of counterarguments to mimetic theory, and some people seem to treat it as a theory of everything. I want to read Girard first and then read his critics.