Fajita Stuffed Chicken is a spicy, flavorful low-carb meal, and it's made in a single pan. Seasoned chicken breasts are stuffed with grilled onions, peppers, salsa, and cheese. Add your own favorite toppings, like guacamole or sour cream, and you've got a complete meal.
Preheat oven to 350 degrees.
In a cast iron skillet over medium heat, add olive oil. Add sliced bell pepper and onion and cook until lightly browned and onions are translucent, about 5 minutes. Remove from heat and set aside.
Butterfly your chicken breasts - hold your hand on top of the chicken breast and slice into the side of the chicken breast, cutting from one side to the other, leaving the opposite side intact. Your goal is to create a pocket for your filling.
Season chicken breasts with salt, pepper, cumin, and paprika. Add about 1 tablespoon of salsa and 2 tablespoons of cheddar cheese to each chicken breast. Then add your cooked bell pepper and onion. Optionally, use toothpicks to keep the chicken breasts closed around the open edge.
Reheat skillet over medium heat. Sear chicken breasts on each side for 2-3 minutes per side, until browned.
Move skillet to oven to finish cooking for 12-15 minutes, or until juices run clear. Remove from oven and allow to rest for 2-3 minutes before serving.
Add any additional toppings to your chicken breasts before serving: guacamole, salsa, more cheese, or salsa.