1Whisk 1 cup plus 2 tablespoons water, sugar, cocoa powder, and salt together in a large bowl.
2Refrigerate mixture until chilled, 30 minutes to 1 hour.
3Pour mixture into an ice cream maker. Freeze according to manufacturer's instructions, about 15 minutes.
Footnotes
Cook's Note:
You can make this without an ice cream maker too. After whisking, pour into a freezer-safe bowl. Freeze for 45 minutes. If it's frozen around the edges, stir vigorously and return to the freezer. Continue checking and stirring every 45 minutes to an hour until frozen to the correct consistency.