Epazote Herb (Chenopodium ambrosioides). A Mexican herb with a very strong taste that has a pungent odor reminiscent of gasoline. It has been used in Mexican cuisine for thousands of years dating back to the Aztecs who used it for cooking as well as for medicinal purposes. Although Epazote is poisonous in large quantities, it has been used in moderation to help relieve the abdominal discomfort (gas) that some people experience from eating beans. It has become a distinct flavor in Mexican cuisine and is used to season a variety of dishes including beans, soups, salads and quesadillas.