Bring sugar, 1 cup water, the peppercorns, cloves, cinnamon stick, star anise, and zest to a boil in a small saucepan.
Reduce heat, and simmer 5 minutes.
For milder flavor, remove star anise, and discard; simmer 10 minutes more.
Remove from heat.
Let cool completely.
Pour through a sieve into a bowl; discard solids.
Syrup can be refrigerated in an airtight container up to 1 month.
