Turn the oven on to 400. Prick the sweet potatoes all over, place in a dish and into the oven. Bake until they are very soft to the touch, the softer the better.
Meanwhile, rub coconut oil or butter inside a deep baking dish such as a souffle dish. Zest and juice the orange and set aside.
Once the sweet potatoes are out of the oven, place them in a cool location such as the fridge, freezer or outside until they are easy enough to touch + peel.
Increase the oven temperature to 450.
Now that the sweet potatoes are mostly ready, strain the garbanzo bean liquid into a large mixing bowl. Reserve the beans for a different use. Whip the liquid with an electric beater or stand mixer. Once soft peaks form, add the maple syrup or your sweetener of choice. Continue to whip until the peaks are stiff, please see the intro. Fold in half of the orange zest, half of the vanilla/rum and half of the salt.
Peel the sweet potatoes and mash them into a deep baking dish such as souffle pan. Mash in the remaining orange zest, vanilla/rum and salt.
In large dollops, add the meringue on top of the sweet potatoes. Place in the oven and bake until the peaks of the meringue are turning golden. Remove and serve quickly as it will start to deflate.