In a bowl, mix together the yolks, cornstarch, sugar, cocoa powder and salt. Then add the 1/3 cup of milk to the mixture. Set aside.

In a medium size saucepan, add the remaining milk along with the cream. Just before the milk and cream mixture was about to boil, turn off the heat.

Ladle the hot milk and cream little by little into the mixture you set aside earlier and mix it making sure everything was incorporated well. IMPORTANT: DO NOT POUR ALL AT ONCE THE HOT MILK AND CREAM INTO THE YOLK MIXTURE! IT WILL SCRAMBLE YOUR EGGS.

Then transfer back your mixture into the pan on a low heat stirring with a whisk constantly. Make sure the heat is low and you are mixing because it might burn under. You will know if the pudding is ready if it starts to resemble the texture of mayonnaise.

When you reach your desired texture, turn off the heat then mix your finely chopped chocolate. If you see that the chocolate is not melting into the pudding, bring it back to a low heat then mix it until everything is incorporated.

Do not be alarmed if there are lumps, just whisk vigorously and it will disappear by then. Serve chilled.