Epazote is the preferred herb in Mexican dishes. It adds a certain earthiness to food, providing a balance with flavors like lime and coriander.
Even though I grew up cooking in the Southwest all my life, I had not heard mention of using this plant for cooking. By the time I could reach the stove and stir the pot, my grandmother and other cooking teachers were using Mexican oregano instead of epazote. I heard about this herb (weed) for the first time while working in a country club in the middle of Phoenix. One of the chefs there introduced me and I am forever grateful.