During the green chile season gas-powered chile roasters, like this one at the Hatch Festival, go almost non-stop. Chile vendors and supermarkets roast 30-40 pounds of peppers at a time, very quickly. For smaller quantities it's not that hard to roast chiles at home, without a fancy roaster. Here's how:
Whether you get your peppers from the local supermarket or pick them fresh in the fields, select large, firm, meaty chiles with no sign of wilting. Wash the peppers before proceeding.
Slit each pepper lengthwise and scrape out the seeds and membranes with a spoon. Protect your hands with gloves or vegetable oil, as the pepper juice can be irritating to sensitive skin. (Some folks skip this step, but we think the seeds are easier to remove before roasting. If roasting with the seeds, pierce the peppers with a knife point near the stem end to release steam as they roast.)
Arrange the peppers in a single layer on a baking sheet. A layer of foil makes later cleanup easier.
Place in the oven, 4-5 inches from the broiler element. The skin will blister and blacken. Turn the peppers as required to blister evenly on all sides. At this point your kitchen will be filled with the mouth-watering aroma of roasting green chile!
If it's a nice day outdoors, and if you have a good gas barbecue grill, you can roast your chile that way. Arrange the peppers in a single layer over high heat, turning them as necessary to evenly blister the skins.
Whichever roasting method is used, the chile skins should be evenly blistered, mostly black. Cover the peppers with a damp kitchen towel for 15 minutes or so to steam them and loosen the skins. You can also put them in a plastic bag to steam after they have cooled a little so as not to melt the bag.
If you're having green chile for dinner tonight, they are ready to use now. Just slip the skins off and chop, stuff, etc. Otherwise,package the cooled peppers in airtight bags for freezing. We prefer to freeze the peppers whole with the skins on, as that seems to result in a firmer texture when thawed. When ready to use, thaw for a few minutes and the skins slip off easily. Drain on a paper towel and you're ready to cook!