1. Bring tamarind, sugar, and 3 cups water to a boil in a 2-qt. saucepan. Cook, whisking constantly, until sugar and tamarind dissolve, about 3 minutes. Transfer tamarind mixture to a bowl and refrigerate until chilled.
2. Whisk in the chile powder and pour into six 3-oz. ice-pop molds (go to www.centralchef.com for a source). Transfer molds to the freezer and freeze until slushy, about 1 hour.
3. Insert a Popsicle stick into each mold and freeze until pops are solid, about 3 hours more. To release ice pops from molds, run the bottom of the molds briefly under warm water.