In a small bowl or liquid measuring cup, stir together the milk and ground coffee. Set aside for 10-15 minutes so that the coffee can flavor the milk.
Filter out the coffee grounds and pour the milk into a medium saucepan.
Whisk in the egg yolks, sugar, cornstarch, and salt.
Add the chopped chocolate.
Bring the pudding mixture to a simmer over medium heat, whisking occasionally to combine the melted chocolate.
Once the mixture starts to simmer, whisk consistently until it thickens, about 6-8 minutes.
Once thickened, pour the pudding through a fine sieve into a bowl to remove any lumps that might remain. Stir in the vanilla extract.
Pour the pudding into the prepared crust and press a sheet of plastic wrap into the top of the pudding. Chill in the fridge until set, at least 4 hours or overnight.