- Heat water, sugar and coffee in saucepan over medium-high heat.
- Whisk to dissolve sugar.
- Bring mixture to a boil.
- Place chocolates in stainless steel bowl.
- Remove boiling liquid from heat, and pour 1 cup over chocolate.
- Allow to stand for 5 minutes.
- Whisk until completely smooth, about 3 minutes.
- Add remaining hot liquid, and whisk until smooth.
- Cool in ice-water bath to temperature of 40 to 45 °F.
- When cold, stir in vanilla.
- Freeze in ice cream freezer.
- Transfer semi-frozen sorbet to plastic container, securely cover and place in freezer for several hours.
- Serve within two days.