1. Combine coffee (or espresso) powder and hot water in small bowl. Let stand until coffee dissolves, about five minutes.
2. Microwave chocolate, sweetened condensed milk, and coffee mixture in bowl, stirring every 10 seconds, until chocolate is melted, about one minute. Stir in vanilla and salt. Let cool.
3. With electric mixer on medium-high speed, whip cream to soft peaks, about two minutes.
4. Whisk one-third of whipped cream into chocolate mixture. Gently fold remaining whipped cream into chocolate mixture until incorporated.
5. Freeze in airtight container until firm, at least six hours or up to two weeks.