ancho chiles (when dried)
Fat, wide, and dark green, the poblano is rich in flavor and mild to medium in heat. Poblanos are one of the most commonly used chiles in Central Mexican cooking, both fresh and dried (ripened, dried poblanos are called ancho chiles).
Named after the Mexican city of Puebla, where they probably originated, poblanos are generally roasted and peeled before use, though they can also be sautéed.
Poblanos are sometimes erroneously labeled as pasillas, a different though similar-looking chile.
Substitute another mild-to-medium green chile, such as Anaheims or jalapeños.
Poblanos are available in most supermarkets. Choose chiles that are shiny and firm pods with strong, uniform color. They should feel dense and heavy for their size; good examples of even the very smallest ones will feel heavier. Avoid chiles that are flaccid, wrinkled, bruised, blemished, or discolored.
Many recipes start out with roasted, peeled poblanos. Here's how to roast them:
If you have a gas stove, coat each chile with a little vegetable oil. Roast each chile directly on the grate of a gas stove over high heat, turning occasionally until it's charred all over. If you don't have a gas stove, you can broil the oiled chiles on a foil-lined baking sheet, turning them often so they char evenly.
Put the charred chiles in a bowl while they're still hot and cover with plastic wrap. Let them rest until they're cool enough to handle, about 15 to 30 minutes. Pull on the stem to remove the seed core. Cut the chile open, flick out any remaining seeds, and turn the chile skin side up. With a paring knife, scrape away the charred skin. Don't rinse the chiles; you'll dilute the flavor.