• In a large saucepan, mix sugar, cornstarch and salt. Whisk in milk until smooth. Cook and stir over medium heat until thickened and bubbly. Reduce heat to low; cook and stir 2 minutes longer. Remove from heat.
• In a small bowl, whisk a small amount of the hot mixture into egg yolks; return all to the pan, whisking constantly.
• Bring to a gentle boil; cook and stir for 2 minutes. Then, reduce heat to low and stir in the dark chocolate until melted. Remove from heat and stir in the vanilla extract.
• Cool for 15 minutes while stirring occasionally.
• Finally, transfer it to a bowl and press plastic wrap onto the surface of the pudding. Do refrigerate it until it's cold. If you desire, you can serve it with whipped cream.

Notes:�

• The plastic wrap should touch the entire surface of the pudding to prevent skin from forming.