3 ounces semisweet chocolate, chopped
1 cup heavy or whipping cream, chilled
2 ounces mascarpone
1 teaspoon sugar
3/4 teaspoon instant espresso powder
1. Set a medium bowl over a small saucepan of simmering water. Add 2/3 of the chocolate to the bowl. Stir until it melts. Remove the bowl from the saucepan, dry the bottom of the bowl and set it aside to cool.
2. In an electric mixer, beat 1/4 cup of the cream with the mascarpone, sugar, and espresso just until smooth. Remove the expresso mixture from the mixer bowl and set it aside.
3. Add the remaining 3/4 cup cream to the mixer bowl. Beat the cream until stiff peaks form. Fold in the melted chocolate.
4. In 2 large parfait or wine glasses, layer the chocolate mixture alternately with the espresso mixture. Top with the remaining chopped chocolate. Refrigerate until serving.