Add the water and sugar in a medium sauce pan, stir everything together and place over medium heat and let it simmer until the sugar has dissolved.
Let it cool completely.
Cocktail:
Add the lime juice, coconut rum, white rum, simple syrup, ice and coconut milk to the blender and blend for 2-3 minutes.
Serve and enjoy!
Notes
The majority of this recipe is in cups instead of ounces like a regular cocktail recipe. The reason I used cups as a measurement, it's simply because I want to appeal to the everyday cook and not a professional bartender.