Ancho 101    When fresh and still green, these mildly hot, heart-shaped peppers are stuffed and made into chilies rellenos. When mature they are dark, rust red, richly flavored, and often dried and ground into chili powder. Peppers become 4 inches long, tapering to a blunt point. Wrinkled skin takes on even more character when dried. May be strung into long ropes or made into wreaths.