Wearing rubber gloves, remove stem and seeds from peppers. Place on baking sheet and cook in a 375ºF oven for 3 - 5 minutes until slightly darkened. Cover with water in a small sauce pan, and bing to a boil, then turn off heat and allow to soak for 30 minutes. Place peppers, cumin and garlic powder in a food processor with 2 1/2 cups liquid (use soaking liquid and added broth or water if necessary). Blend until smooth. Add to tamale meat or chili or other dishes.