2 tbsp. extra-virgin olive oil
1 c. medium onion, diced
1 c. red and green bell pepper, diced
Freshly ground black pepper
4 boneless, skinless chicken breasts
1 c. shredded cheddar
2 tbsp. Cajun seasoning
Preheat oven to 350°. In a large ovenproof skillet over medium heat, heat oil. Add onions and peppers and cook until soft, 5 minutes. Season with salt and pepper. Remove from heat and let cool slightly.
With a sharp paring knife, create a pocket in each chicken breast. Stuff each with vegetable mixture, then top with cheddar. Season chicken all over with Cajun seasoning, salt, and pepper.
Add chicken to skillet and bake until cooked through, about 25 minutes.