Heat olive oil in a large skillet over medium heat. Add the sliced chicken and season with salt and black pepper. Cook until golden brown on both sides, then remove from the pan and set aside.
In the same pan, add the chopped onion, minced garlic, and sliced bell peppers. Sauté for about 3–4 minutes until softened. Stir occasionally to prevent burning.
Pour in the chicken broth and heavy cream, stirring well. Sprinkle in the Italian seasoning and let it simmer for 3–4 minutes until slightly thickened. For another creamy dish, try Chicken Alfredo Casserole.
Return the cooked chicken to the pan and mix well. Stir in the grated Parmesan cheese and let it cook for another 2–3 minutes until the sauce fully coats the chicken and peppers.