Dried chiles have a rich and concentrated flavor. They can pack a spicy punch. Peppers often become hotter as they ripen and they can be at their hottest when they're dried. As a rule of thumb, the smaller the pepper, the spicier it will be. To tone down the heat, remove the seeds and white ribs. To prepare dried chiles, it is best to either soak the chiles in warm water until soft or grind the peppers in a food processor. The method you choose will depend on its application in a dish. Look for dried chiles in the Latin section in your market. Here is a list of the ones you are most likely to find.
Ancho: These are dried poblano chiles. They are brownish-black in color with a flavor similar to raisins. They are present in a number of Mexican dishes including tortilla soup and salsas. Scoville Units: 1,000-2,000
Guajillo: These chiles are smooth and reddish-brown. Guajillo chiles have a sharp flavor and are moderately spicy. Soak and puree this chiles and add to a Mexican mole sauce. Scoville Units: 2,500-5,000
Cascabel: These small cherry shaped chiles make a rattling sound when shaken, hence their nickname "rattle chile." They have a smoky flavor and are delicious added to ground meat for tacos or to chili. Scoville Units: 1,500-2,500
New Mexico: These chiles have an earthy flavor. They are the star ingredient in the state's red enchilada sauce. Scoville Units: 2,500
Pasilla: This is the dried version of the chilaca chile. Pasilla are often mislabled as ancho because of their similar appearence. They are thin and long with a slightly bitter flavor. Scoville Units: 4,000
Chipotle: A smoked and dried jalapeno pepper, often found canned in adobo sauce. It has a smokey flavor reminiscent of barbecue. For ideas of how to use chipotle peppers, read one of my previous posts. Scoville Units: 10,000
De Arbol: These thin red chiles remain the same color even after drying. They are wonderful tossed whole in dishes like kung pao chicken. Scoville Units: 50,000-65,000