In medium skillet, with 2 Tablespoons of cooking oil, toast pepper (ancho and cascabel) until golden crispy. Remove from skillet and set aside. In blender add garlic, cumin, salt, black pepper, roasted peppers, tomato puree. Blend at medium speed for approximately 3 minutes, add 2 1/2 cups of water and blend again for a couple of minutes - set aside.
Put 2 tablespoons of oil in a skillet. Get oil hot and add the salsa in blender. Stir and cook for 15 minutes so spices can cook with the sauce. Set aside.
Dip tortillas (one by one) in hot skillet with the 1 1/2 cup oil until soften. First dip in oil and second dip tortilla in the Ancho Sauce until all of the tortillas are done.
Fill each tortilla with the queso and onion mixture, roll into an enchilada. Serve 2 or 3 enchiladas in a plate and spoon on top salsa de Chile Ancho and sprinkle with additional queso and chopped onion.