Preheat the oven to 350°F. Spray a 9x13-inch baking dish with nonstick cooking spray.

In a mixing bowl, combine the condensed cream of chicken soup, chicken broth, and minced garlic. Whisk well until smooth.

Season both sides of the chicken breasts with the grated Parmesan, salt, and pepper.

Arrange the seasoned chicken breasts in the prepared baking dish. Top each breast evenly with 2 slices of Swiss cheese.

Pour the cream of chicken soup mixture evenly over the chicken and cheese. Use a spatula to spread it evenly across the dish.

Sprinkle the dry stuffing mix evenly over the chicken and sauce. Completely cover the surface with stuffing.

Drizzle the melted butter over the stuffing layer.

Cover the baking dish tightly with aluminum foil. Bake for 40 minutes.

Remove foil and continue baking 15-20 minutes more until the stuffing is golden brown and the chicken breasts reach an internal temperature of 165°F.

Let casserole rest 5 minutes before serving. Garnish with chopped parsley if desired.