Chocolate-Earl Grey Sorbet

4 Earl Grey tea bags
1 cup unsweetened Dutch-process cocoa powder
1 ounce good-quality bittersweet chocolate, finely chopped

4 cups water
3/4 cup sugar

Bring water and sugar to a boil in a large saucepan. Add tea bags and remove from the heat. Cover the pan and steep for 15 minutes.

Remove the tea bags and discard. Place the pan over medium-high heat and slowly add cocoa, whisking until smooth. Bring to a boil, reduce heat to low and simmer until the mixture thickens slightly, about 20 minutes.

Remove the pan from the heat. Add chocolate and stir until completely melted and smooth. Pass through a strainer into a medium bowl. Cover and refrigerate until thoroughly chilled, at least 2 hours.

Transfer the mixture to an ice cream maker and freeze according to manufacturer's directions. Break into chunks and process in a food processor until smooth. The sorbet should be thick and icy after processing. If you prefer it firmer, place in the freezer for 30 minutes.