Step by step: Preheat the oven to 375 degrees F (190 degrees C). Bring broth to a boil in a large saucepan. Add chicken breasts and cook until very tender, no longer pink in center and juices run clear, 15 to 20 minutes. An instant-read thermometer inserted near the bone should read 165 degrees F (74 degrees C). Remove the chicken to a plate, keeping the broth in the pot. Remove and discard bones, fat andskin. Chop the meat and set aside.
Add the rice to the broth and bring to a boil over medium-high heat. Reduce heat to medium-low, cover and simmer until rice is tender and stock is absorbed, 20 to 25 minutes. Put aside.
Heat the oil in a large skillet over medium-high heat. Add peppers, onions, jalapenos and garlic; sauté until slightly tender, about 5 minutes.
Combine chicken, rice, vegetables, black beans, salsa, fajita seasoning, salt and pepper in a large mixing bowl. Transfer to a large casserole dish and top with cheese.
Bake in preheated oven until golden and bubbly, about 30 minutes. Let stand 10 minutes; serve with sour cream and tortilla strips on top. Enjoy!