Fry chilies in a little of the oil; remove and soak in hot water 25 to 30 minutes. Drain, reserving 1 cup water. Seed the chilies and combine in blender container with onion, reserved water, tomato, garlic, cumin and salt. Blend smooth, return to pan with a little oil and cook about 10 minutes over medium heat. Use with enchiladas or with shredded or thinly sliced roast pork. Makes enough for about 12 enchiladas. "This is Mariquita Masterson's version of the red chili gravy traditionally served with enchiladas. Heat sauce before using. To make enchiladas, spread grated Chihuahua or Monterey Jack cheese on corn tortillas and roll up tightly; place in casserole, seam side down, pour heated sauce over them and heat in 400-degree oven about 10 minutes. Top with finely chopped onion and Mexican sour cream. "