Roughly chop the chocolate or break it into pieces. Remove 6 tbsp. from the milk and stir in a bowl with pudding powder and sugar until smooth.
Bring the rest of the milk to the boil in the pot (caution: it boils over quickly!). Melt chocolate in it while stirring constantly. Take the pot off the stove.
Stir the mixed custard powder evenly with a whisk so that no lumps form (see fig. 2). Bring to the boil while stirring, simmer for about 1 minute.
Pour the custard into a bowl and place cling film on top to prevent skin formation (see Fig. 3). Place in a cool place for approx. 1 hour. Or fill into four cold rinsed moulds (200 ml each) and refrigerate for at least 3 hours.
Remove the foil and whip the pudding in the large bowl with a whisk until it is creamy and firm. Pour into cappuccino cups or dessert bowls and dust with cocoa.