Season both sides of the chicken breasts with salt and black pepper.
Heat olive oil in a large skillet over medium-high heat.
Add the chicken breasts to the skillet and cook for 5-6 minutes on each side, or until golden brown and cooked through. Remove chicken from the skillet and set aside.
Reduce heat to medium and add the minced garlic to the skillet. Sauté for 1 minute until fragrant, stirring frequently to avoid burning.
Pour in the chicken broth and use a wooden spoon to scrape up any browned bits from the bottom of the skillet.
Add the heavy cream, Parmesan cheese, Italian seasoning, and crushed red pepper flakes. Stir well to combine and bring the sauce to a gentle simmer.
Add the unsalted butter and stir until melted and the sauce is slightly thickened, about 3-4 minutes.
Return the cooked chicken breasts to the skillet, spooning the sauce over them. Simmer for an additional 2-3 minutes to heat through and allow flavors to meld.
Sprinkle chopped fresh parsley over the chicken and sauce before serving.