Preheat the oven to 325 degrees F. Coat a baking dish with cooking spray.
Arrange the cabbage wedges in the baking dish, then scatter the carrots and onions around the cabbage.
Pour the chicken broth into the pan. Sprinkle the butter pieces over the cabbage and season everything with salt and pepper to taste.
Cover the dish with foil, and bake for 2 hours. Uncover the dish halfway through the bake time and use tongs to carefully flip the cabbage wedges over.
Increase the oven temperature to 425 degrees F. Uncover the dish and bake for 15-20 minutes or until cabbage starts to brown at the edges.
Sprinkle with parsley, then serve.