In the case of Braggs, which is our brand of choice, the fungi are grown on beet and cane molasses to provide the optimal flavor and nutrients. It’s similar to bread yeast, however the product has been dried out and pasturized to make it shelf-stable, resulting in the flaky yellow product that’s commonly sold at health food stores.
We use about 2 tablespoons of nutritional yeast to season popcorn popped on the stove (so we know it’s low sodium and not full of excessive flavoring additives). It’s as versatile as parmesan though – a little on top of zoodles will add a cheesy kick, which a few tablespoons in soup adds a nutty depth. My vegan friends often use it in larger quantities in the place of cheese for mac and cheese, risotto, and other cheesy casserole dishes. A quick Google search will bring up hundreds of recipe ideas!