Arrange chicken in a lightly greased 9x13 inch baking dish. In a medium bowl, combine the soup, wine, garlic powder, cayenne pepper, mustard seed and sour cream and blend together; set aside.
Top each chicken breast with a slice of Swiss cheese and pour sour cream mixture evenly over the chicken. Crush the bag of croutons and sprinkle evenly over all, then drizzle with melted butter.
Bake at 350 degrees F (175 degrees C) for 50 minutes, or until chicken is cooked through and juices run clear.
