Epazote, Mexican Tea, Chenopodium ambrosioides L., also called wormseed, is used to expel worms (only in the hands of a skilled holistic health care practitioner, overdoses are common and severe).

Food:  Epazote is used sparingly in soup, tacos, black beans, mushrooms...It is pungent, an acquired taste in time you will really enjoy.

Plant used to reduce fevers, also as a spring tonic; leaves were crushed and used as a poultice to treat headache; leaves were decocted in milk and used  to treat worms; plant used as poultice on edema; Seeds used as tonic tea; seeds to treat worm infestations.  Plant used to quell toothache. 

WARNING: overdose extremely toxic.  THERE IS A MOVEMENT IN MEXICO TO BAN THE USE OF THIS PLANT.  Difficult situation given traditional uses.  I found the plant used in almost every rural Mexican home.
Epazote flowers and seeds.

BEAN SOUP: I use 6 or 7 leaves in 2 quarts of bean soup, add near the end of the cooking.

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Mexican Medicine
Medicinal Plants of Texas