If you are looking for an elegant and delightful tasting chocolate dessert, then this chocolate mousse will quickly become your favorite! Smooth and creamy, you will scrape out every last bite!
In a double boiler, or in a metal bowl over a simmering pot of water, combine the egg yolks, sugar, and coffee. Be sure to keep the water at just a simmer. Whisk the egg mixture constantly until thickened and the sugar has all dissolved, about 7 minutes. On a thermometer, it should reach 160°. Remove from the heat and set aside.
Melt the chocolate and butter in the microwave in 20 second intervals until fully melted. Add the chocolate into the egg mixture and whisk until smooth. Set aside to cool to room temperature.
When the mixture is cooled, whip the heavy cream until stiff peaks form. Fold 1/3 of the whipped cream into the chocolate mixture and then fold the chocolate mixture into the remaining whipped cream until no streaks of white remain. Transfer to a large ziplock bag and snip off the corner. Pipe into six 4-ounce dessert cups or ramekins. Cover the cups with plastic wrap and chill for at least 4 hours before serving.
Garnish with a dollop of whipped cream and a mint leaf.