Add the coconut milk and sugar to a small sauce pot. Bring to a low boil and then reduce the heat to a simmer. Simmer on low for 1 hour and 30 minutes to 2 hours. Once the milk has thicken and reduced by half remove from the stove and allow to cool. Stir in the vanilla Pour the milk into a glass jar and store in the fridge until ready to use or up to two weeks.