A dried Mexican chile that’s an essential ingredient in classic mole Poblano. It is fairly mild in heat, with slightly anise-y notes, with the flavor of dark fruits like prunes and cooked cranberries, and an earthiness reminiscent of coffee or bitter chocolate.
Substitute ancho chiles.
Mulato chiles resemble anchos in appearance (and are often mislabled as anchos). You can tell the difference by tearing a chile in half and holding it up to the light: the ancho is reddish and somewhat translucent, while the mulato is almost opaque black-brown. To be sure you’re getting the right chiles, buy them from a reliable chile specialist.