In a large, heavy-bottomed pot, heat coconut oil over medium heat. Add onion and cook, stirring occasionally, for 5 minutes.
Meanwhile, cut the sweet potato into small cubes. Add the garlic and spices to the onion and cook for 1 minute. Tip in the sweet potato, crushed tomatoes, broth and beans. Stir well to combine.
Increase heat to medium high. Bring the chili to a simmer and cook for 1 hour. Stir occasionally.
Test sweet potato for doneness, and if it is soft enough to be mashed with a fork, yet still holds its shape, the chili is ready for the final step.
Add the salt and the maple syrup. Sprinkle the cornmeal over the top and stir well. Lower heat and cook for an additional 15 minutes, stirring often. Chili will thicken.