To easily deseed the chiles, use kitchen shears or a paring knife to remove the stem, then split the chiles open lengthwise. With your fingers, gently scrape out the seeds and veins. Use gloves to protect your hands from the chiles’ stinging oils. Chilhuacle is a chile native to Oaxaca but often hard to find elsewhere. A good substitute for it is a combination of more pasilla negro chiles and some cascabel chiles. It’s important to have proper ventilation to char the chiles (and particularly the seeds) as they can produce strong fumes. If possible, do the step of burning the seeds on fire outdoors. Mole can be refrigerated in an airtight container for 3 to 4 days or frozen for 3 to 4 months.