Preheat a grill to medium-high heat and oil the grates.
In a large pot, add the sweet potatoes and cover with cold salted water. Bring them to a boil over medium heat. Lower the heat and simmer until you can pierce each potato with a paring knife and there is little to no resistance, approximately 25 to 30 minutes. Do not overcook.
Transfer the sweet potatoes to a large bowl of cold water to halt their cooking process. Once the potatoes are cool, drain well. Peel the potatoes and cut them lengthwise into thick wedges, about 6 wedges per potato. Put the potatoes into a large bowl and coat them with olive oil. Add the brown sugar, cayenne, salt, pepper, cinnamon and cloves and toss to evenly coat. Put the wedges on the preheated grill. Cook until they are heated through and caramelized, approximately 3 to 4 minutes per side. Serve them as they are, or with a side of mint and cumin aioli, if desired.
This side dish reminds me of the traditional street food served in Malaysia (my father's hometown) and Taiwan (my mother's hometown). Street vendors or "hawkers" often sell roasted whole sweet potatoes, and you can see people walking down the street with small foil packets of steaming sweet potatoes in their hands. These fries are an updated version of the classic street snack to serve alongside the curry beef burgers.