Add sugar to a pot over low/medium heat and heat until sticky, stirring frequently for about 10 minutes
Add water and stir to combine
Add the remaining ingredients (orange rind, lemon rind, lime rind, cinnamon sticks, coriander, and nutmeg), stir and increase heat to medium until it reaches a low boil
Reduce heat to a simmer for 10 minutes, stirring occasionally
Strain and store in an airtight container in the fridge for up to 2 weeks
To use: add 3 tablespoons over ice to a 12 oz glass and top with sparkling water, adjust to taste
