Fresh chiles and bell peppers can be roasted over a gas flame or on a tray under the broiler. Keep turning so the skin is evenly charred, without burning and drying out the flesh. Transfer the charred peppers to a plastic bag, tie the top closed and let steam until cool to the touch, about 15 minutes. (If you are rushed, you can place the bag in a bowl of iced water to speed things up.) The best way to peel is just to pull off the charred skin by hand and then dip the peppers briefly in water to remove any blackened bits. Do not peel the pepper under running water since that will wash away flavorful juices. Once peeled, cut away stems, seeds and veins.