1. Preheat oven to 350 degrees F. In a large skillet over medium heat, combine first 6 ingredients (through cumin), bringing the mixture to a boil. Reduce heat and simmer uncovered for 5 minutes.
2. Stir in beans. Spread 1/3 of the bean mixture over the bottom of a 13x9" pan. Top that with 1/2 the tortillas, overlapping as necessary and 1/2 the cheese.
3. Add another 1/3 of the bean mixture, then remaining tortillas and bean mixture. Cover and bake for 30 minutes or until heated through.
4. Sprinkle with remaining cheese and let stand for 10 minutes. Garnish with shredded lettuce and chopped tomatoes.
For more of a Mexican flair, add slices of avocado on top or your favorite guacamole. This is wonderful if you're in a south-of-the-border mood. Add a little Spanish rice and a glass of your favorite sangria for a complete and tasty meal.