Chile is the most generic word I have heard used for such a large number of capsicum peppers. When I find a recipe on the Internet that I want to try, and it just says "chiles" as an ingredient, I use what I have at hand keeping in mind how hot I want it to be. Hopefully, the list below will also help you realize how hot the Mexican recipe was meant to be if a specific type of chile is indicated. Keep in mind that since there is a wide range of chiles in Mexico, many times a specific chile will be needed in a recipe as it imparts a particular flavor and taste to that dish; changing the type of chile used produces a different recipe than what is generally intended.
As a rule, the smaller the chile, the more concentrated the heat.
The heat of fresh chiles ranges greatly but these are the most common, from the mildest to the most fiery.
- Anaheim or California: long, slender and light green in color. Can range from mild to quite hot. Can also be found canned as whole green chiles and diced green chiles.
- New Mexico: Long green chile resembling Anaheim, but hotter.
- Poblano: Most used fresh green chile. Generally larger that Anaheim, it's dark green and shiny with broad shoulders, tapering to a rounded or pointed bottom.
- Guëro: Pale yellow, waxy, small hot chile. Can also be found as the milder banana and Hungarian wax chile, which are longer at about 4 inches (10 cm) long.
- Jalapeño: Dark green, plump hot chile about 2 to 3 (5 to 8 cm) inches long with a rounded bottom. Used raw in salsas as well as cooked in sauces. Can also be found pickled and canned.
- Serrano: Small, slender, light green hot to very hot chile used mainly in fresh salsas or cooked sauces. Often used interchangeably with jalapeños.
- Habanero: Small, very hot found in shades of green, yellow, orange and red. Lantern shaped with indentations and irregularities.
Dried chiles are mainly used for cooked sauces. Buy in bulk and look for those that are blemish-free and with good color. The heat scale goes from California, Ancho and New Mexico on the mild side, followed by Mulato, Guajillo, and Cascabel, with Chile de arbol and Chipotle as offering the most heat.
- Ancho: A dark red to almost-black dried poblano chile, with wrinkled skin. It is also called chile pasilla in some places. Generally toasted then reconstituted in hot water to soften the skin before being pureed in sauces. These can be mild to hot.
- California: shiny dried chile with smooth red skin which can range from mild to slightly hot.
- Mulato: Very dark, almost black dried chile very similar to and often mistaken for an ancho chile. Used in moles.
- Guajillo: Medium to long dark red dried chile that is quite hot and very popular.
- Cascabel: Dried reddish brown chile which is mildly hot with a nutty flavor. Round in shape and cherry-sized or larger. When shaken, the seeds inside rattle and thus its name.
- Chile de arbol: Small, thin dried chile that is very hot.
- Chipotle: Dried smoked jalapeño with a brown leathery skin. It is very hot and often used canned in a seasoning mixture called adobo. Chipotles are popular.
Important note: Pure ground chile powder is labeled with the name of the chile and is unseasoned. Commercial chili powders (note it is chili with an "i" and not chile with an "e") are blends of ground chile, cumin, oregano, garlic and other spices generally used in chili (as in the Tex-Mex dish, beans and stews which is not the same thing. Be extra careful when selecting powders at the supermarket so that you buy the one you were looking for.