In a non-stick pan with a little water (1 tbsp.), sauté the peppers, garlic, and onion for about 3 minutes, or until softened. Add the black beans, tomatoes, chili powder, and cumin. Set aside.
Spray a 9 X 13-inch baking pan with non-stick spray. Line the bottom with a layer of tortillas (you may cut some of them to fit). Make sure you cover the entire bottom of the pan.
Combine the refried beans and salsa and heat until bubbly. Spread half of them evenly over the tortillas. Cover the refried beans with half of the black bean mixture.
Add another layer of tortillas and repeat the layers of refried beans and black beans. Cover with a final layer of tortillas, pour the enchilada sauce over the top, and sprinkle with black olives (if desired). Cover and bake for about 30 minutes or until hot throughout. It will be easier to cut if you allow it to cool for about 10 minutes before serving.
Notes
Fresh corn is a great addition to this. I use about 2 cups of uncooked (or frozen) corn and add it as one more layer. You may need a deeper pan, though.Nutrition per serving will vary depending on brand of salsa, sauce, and beans used. Sodium level assumes canned, salted beans and sauce.