Rinse the cranberries under cold water. In a small saucepan, combine the cranberries, water, sugar, cloves, star anise, and cinnamon stick.
Place the saucepan over medium heat and bring the mixture to a medium, stirring occasionally until the sugar dissolves. Simmer the mixture on low heat for about 10-15 minutes, or until the cranberries burst and the syrup thickens slightly. Stir occasionally to prevent sticking.
Remove the saucepan from the heat once the syrup reaches your desired consistency.
Strain the syrup through a fine-mesh sieve or cheesecloth into a heatproof container or bowl, pressing down on the cranberries gently with the back of a spoon to extract the liquid. Discard the solids (cranberry pulp and spices).
Let the spiced cranberry syrup cool completely at room temperature. Once cooled, transfer it to a clean glass jar or bottle with a tight-fitting lid.
Store the syrup in the refrigerator. It should keep well for about 2-3 weeks.