Step 1

In a medium saucepan, bring 2 cups of half and half to a simmer (do not boil).

Step 2

Add both sugars and vanilla. Cook until the sugar is completely dissolved, stirring constantly to prevent scalding. Stir in the butter until melted. I

Step 3

n a small bowl, whisk together the remaining half and half with the cornstarch and cocoa powder. Slowly add the cornstarch mixture to the half and half whisking constantly.

Step 4

Continue cooking until the mixture has thickened and coats the back of a spoon.

Step 5

Stir in the chopped chocolate until melted. Transfer the mixture to a bowl and cover with plastic wrap being sure the plastic wrap is touching the top of the pudding. (This will prevent a skin from forming.) Refrigerate for 2 hours or up to 24 hours.