Remove 1/3 of the milk and mix well with the starch, cocoa powder and sugar.
In the meantime, bring the milk to the boil. Now add the stirred up and bring to the boil again.
Vanilla pudding is delicious too. For this you take the same amount of sugar and starch, 1 teaspoon of ground vanilla and a pinch of turmeric (because of the color). Is prepared as described above.