How to Make It
Line a sieve with cheesecloth. Put the chocolate in a heatproof bowl. In a medium saucepan, combine 1/2 cup of the sugar with the coffee and 1 3/4 cups of water and bring to a boil. Simmer over low heat for 4 minutes, stirring. Strain the coffee over the chocolate; whisk until melted. Let cool, then refrigerate for at least 2 hours or overnight.
In a medium bowl, using a hand mixer, beat the cream with the remaining sugar at medium speed until soft peaks form. Whisk the chilled mocha mixture until smooth, then fold in the whipped cream. Pour the mocha mixture into the ice pop molds and freeze for at least 4 hours. If using hazelnuts, press the frozen ice pops into the chopped nuts and return to the freezer for at least 30 minutes before serving.