Preheat your oven to 375°F (190°C).

Season the chicken breasts with Cajun seasoning, salt, and black pepper.

In a large oven-safe skillet, heat olive oil over medium-high heat. Add the chicken breasts and sear for 5-6 minutes on each side until golden brown. Remove from the skillet and set aside.

In the same skillet, add diced onion, bell peppers, and garlic. Sauté for 3-4 minutes until the vegetables are tender.

Lower the heat and add heavy cream to the skillet, stirring to combine with the vegetables. Bring to a gentle simmer.

Stir in shredded cheddar cheese until melted and the sauce is creamy.

Place the seared chicken breasts back into the skillet, spooning the creamy sauce over them.

Transfer the skillet to the preheated oven and bake for 25-30 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).

Once done, remove from the oven and garnish with fresh parsley if desired.