Chicken Wild Rice Stuffed Red Peppers

Bring chicken broth to a boil in a saucepan; add wild rice. Reduce heat to medium-low, cover, and simmer until the rice is tender, 55 minutes. Remove from heat and cool for 5 minutes. Preheat oven to 400 degrees F (200 degrees C). Spray a 9x13-inch casserole dish with cooking spray. Mix mushroom soup, chicken, carrot, onion, and red pepper flakes in a bowl; fold in wild rice. Arrange red bell pepper halves in the prepared casserole dish. Fill each half with chicken-rice filling. Cover casserole dish loosely with aluminum foil. Bake in the preheated oven until filling is heated through and bubbling, about 45 minutes.