Melt the chocolate in a double boiler over medium-low heat. Add vanilla and salt.
In a medium saucepan, whisk together egg yolks, maple syrup, and 3/4 cup heavy cream. Heat over medium-low heat, whisking, until mixture coats back of spoon, 3 to 4 minutes. Do not let it boil.
Remove from heat; whisk in melted chocolate mixture.
Strain into a bowl, just to be sure any cooked egg bits are removed.
Set aside to cool to room temperature. Do not refrigerate. The mixture should be cool, but still smooth and somewhat fluid.
Whip the remaining 1ΒΌ cups heavy cream to stiff peaks.
Fold about one-quarter of the whipped cream into the cooled chocolate custard mixture until completely combined.
Gently fold the remaining whipped cream into the chocolate mixture until no streaks remain. Take care not to overmix.
Spoon into serving dishes and refrigerate for 2 to 4 hours, or until well chilled.
