Since we're here, if you want to fully explore that rabbit-hole I recommend getting The Noma Guide To Fermentation. If you want something simple and useful, try

Since we're here, if you want to fully explore that rabbit-hole I recommend getting The Noma Guide To Fermentation. If you want something simple and useful, try lacto fermenting celery. Celery is a magically useful ingredient in cooking, and fermentation extends its shelf life significantly while giving you a variant to use (the liquor).