Heat the oven to 375 F. Lightly coat a baking dish with cooking spray.
Using a fork, poke several holes in the sweet potatoes. Bake until the potatoes are soft, about 1 hour. Remove from the oven and set aside. Peel when cool to the touch.
Place the banana halves in the prepared baking dish. Bake uncovered until the fruit is soft and juicy, about 15 minutes. Remove from the oven and pour the orange juice over the bananas. Stir to scrape the drippings and mash the bananas well.
In a large mixing bowl, add the bananas, sweet potatoes, spices and brown sugar. Using an electric mixer, blend until smooth.
Transfer to an ovenproof serving bowl and return to the oven. Bake until warmed through. Garnish with chopped parsley and serve.