In a large saucepan or pot over medium heat, add the coconut sugar, sweetened condensed milk, maple syrup, ghee, and coconut milk. Whisk and cook until the mixture is smooth and the sugar crystals have started to dissolve, about 3 minutes.
Turn the heat up to medium-high and bring the mixture to a boil. Whisk constantly, cooking for 8-10 minutes to thicken the caramel. Since the coconut sugar is dark, it will be harder to tell when the caramel is done. To test the caramel, use an instant read or candy thermometer and continue whisking and stirring the caramel until it reaches about 235 degrees. It is important you cook the caramel to this temperature and until it has thickened, or your tart will not set.
Remove from the heat, add the vanilla and salt, and stir to combine. Immediately pour it into the cooled tart shell. Transfer to the fridge and allow the caramel to fully set for at least 2 hours or overnight. If you are in a pinch for time, set it in the freezer for one hour.
Once the caramel is fully set, start the ganache.