In 12-inch nonstick skillet, heat oil over medium heat. Add onion, poblano chile and serrano chile. Cook 6 to 8 minutes, stirring occasionally, until vegetables are softened. Stir in taco seasoning mix, tomatoes, broth and salt. Heat to simmering. Stir in rice; remove from heat. Let stand 2 minutes to allow rice to absorb most of the moisture. Add chicken and cheese.