Stupid question: is the "nutrient broth" mixed with the agar, then poured into the dish? The overall procedure is a little unclear to me, and the article seemed

Stupid question: is the "nutrient broth" mixed with the agar, then poured into the dish? The overall procedure is a little unclear to me, and the article seemed to take it for granted. I'd always been under the impression that the agar itself was food for the microbes, which is... silly in retrospect.