1 cup sugar
2 cups water
1/2 cup cocoa
4 ounces semisweet chocolate
Combine sugar and water in a medium saucepan. Bring to a boil. Remove from heat and add chocolate and cocoa. Whisk until melted and smooth.
Prepare a large pan or bowl filled with ice water(water and ice cubes). Return saucepan to heat and bring to a boil again. As bubbles break across the surface, remove from heat. Place pan in ice water bath to cool for 10 minutes. Pour sorbet into an airtight container and freeze for 3 hours.
Remove from freezer and beat mixture for 1 minute. Return to freezer for 3 hours. Repeat beating and freezing twice more until sorbet is smooth and light.
Serve in small scoops with cake, fruit or meringues.