1In a medium saucepan, combine the sugar, cocoa powder, and cornstarch.
Gradually whisk in the milk until the mixture is smooth.
Place the saucepan over medium heat and cook, stirring constantly, until the mixture thickens and comes to a boil.
Once boiling, continue to cook for an additional 1-2 minutes while stirring.
Remove the saucepan from the heat and stir in the vanilla extract.
Pour the pudding into individual serving dishes or a large bowl.
Allow the pudding to cool slightly, then cover with plastic wrap, pressing it directly onto the surface to prevent a skin from forming.
Refrigerate for at least 2 hours or until fully chilled.
Serve and enjoy your homemade chocolate pudding.