In a heavy saucepan combine chocolate and coffee. Heat gently over low heat until the chocolate starts to melt; set aside. In a medium bowl whisk together egg yolks, sugar and salt until well blended; set aside. In a medium saucepan, heat milk until bubbles begin to form around edge of pan (do not boil).
Gradually whisk about half of hot milk into egg yolk mixture. Add yolk mixture to saucepan. Cook and stir continuously with a wooden spoon over medium heat until mixture just coats the back of a clean metal spoon (enough so that a finger run through the sauce will leave a clean trail). Remove pan from heat.
Immediately pour the custard through a fine - mesh sieve, straining over the partially melted chocolate. Whisk until smooth. Transfer to a large mixing bowl and let cool, stirring occasionally, until mixture is about 96 degrees F.
In a chilled bowl beat 2 cups of cream until soft peaks form. Using a rubber spatula, gently fold half of the whipped cream into the chocolate mixture until no white streaks remain. Gently fold in remaining whipped cream. Spoon the mousse into sixteen 2 - ounce dessert cups. Cover and chill for at least 3 hours or up to two days.
To serve, beat remaining 1/2 cup heavy cream until soft peaks form. Spoon on top of each serving. Add fresh strawberry and, if desired, chocolate shavings.