When selecting fresh chiles, make sure that the skin is smooth and they are firm to the touch.  Once they become wrinkled, they develop an earthy taste and their crisp texture and fresh flavor are gone.  Use fresh chiles as soon as possible.  They can be kept, however, for up to two weeks if wrapped in a dry cloth or paper towel inside a paper bag in the refrigerator. 

Charring fresh chiles enhances the flavor of the flesh.  Place the firm, fresh chile directly over an open flame or under a broiler until blistered and charred.  Immediately put the charred chiles into a plastic or paper bag and set aside to sweat for about 10 minutes.  Peel off the blackened skin (don’t worry about picking off every bit of skin) and use in your favorite recipe. 

When selecting dried chiles, buy loose instead of packed whenever possible.  Choose chiles that are still a little flexible and not totally dried out.  Before using dried chiles, place them in a warm skillet and heat until they become pliable or for about 2 minutes.  Store dried chiles in a cool, dry place or keep them in your freezer in zip-lock freezer bags.

To reconstitute, place the toasted, dried chiles in a saucepan and cover them with boiling water.  Weight them with a small dish to keep them submerged and let them sit for 50 to 60 minutes, or until soft.

The easiest way to control the flavor and heat of dishes containing reconstituted dried chiles is to make them into purées.  They can be added to dishes in increments until the desired balance of flavor and heat is reached.