Also know as Savoury Yeast Flakes. It’s a fermented and deactivated yeast, which means it isn’t going to grow (and has nothing to do with brewer’s yeast or bakers’ yeast). It has a creamy cheesy flavour and I’ve used it in a few recipes to create a cheese flavour. Vegans use it as a condiment and a cheese substitute, and to also add additional protein and vitamins to their diet (it’s a complete protein). Nutritional yeast flakes are free from sugar, dairy, grains and gluten. Do not confuse it with yeast extract (MSG). Purchase from health food stores or in the health food aisle of supermarkets.