Combine the coconut milk, vanilla bean and seeds, and brown sugar in a saucepan. Heat over medium-high heat until the sugar has dissolved. Remove from the heat. Add the cardamom, cinnamon, and salt. Allow to cool completely and place in an airtight container. Store in the refrigerator overnight. Can be stored in the refrigerator for up to two weeks.
Add coffee grounds to an airtight container along with the cinnamon stick and cardamom pods. Pour in the water, swirl to evenly wet all the grounds, and loosely cover for 3 minutes.
Take the lid off, add the ice and salt, and swirl. Pour in the cold water and stir to evenly spread everything, then cover tightly and place in the fridge for 8-12 hours.
Remove from the fridge and filter out the coffee from the rest of the ingredients, makes about 1 ¼ cup. Coffee filters work well, but any method to remove most of the grounds from the coffee is fine. Mix a ½ cup of the coffee with ½ - 1 tbsp of spiced coconut milk.