1. Preheat oven to 425°. Brown chicken in a large skillet over medium heat, stirring often, 7 minutes or until chicken is no longer pink. Add onion and bell pepper, and sauté 3 minutes or until vegetables are tender. Drain. Stir in beans, tomatoes, cilantro, and salt.
2. Pour chicken mixture into a lightly greased 13- x 9-inch baking dish. Sprinkle with 1 1/2 cups cheese. Stir together buttermilk and cornmeal mix, and spoon over cheese; sprinkle with remaining 1/2 cup cheese.
3. Bake at 425° for 25 to 30 minutes or until browned.