Once relatively unknown outside of its home area, the Hatch green chile has become a cult item in Southern California. But what exactly is a Hatch chile?
There is no chile variety called Hatch. Hatch chiles include a whole family of long green peppers from the species Capsicum annuum (the same peppers when fully mature turn red and are dried). They range tremendously in spiciness and flavor. You may have seen Anaheim chiles in the supermarket that look just the same, but they are an exceedingly bland member of the clan.
Instead, the name "Hatch" refers to where these chiles are grown: the area around a tiny town in the Mesilla Valley in southwestern New Mexico, just outside of Las Cruces. Similar green chiles are grown all over the state, and each area has its own passionate supporters, but Hatch has become the most recognized.
That popularity has led to claims of widespread copycatting. While there are a lot of chiles grown in Hatch, there almost certainly aren't enough to account for everything that is sold under that name these days.