Finely chop the chocolate. Separate egg. Beat the egg white and 1 pinch of salt until stiff with the whisk of the mixer, gradually adding 2 tablespoons of sugar. Keep beating until the sugar is dissolved.
Mix 2 tablespoons sugar, starch and 6 tablespoons milk. Bring 400 ml milk to the boil. Stir in the starch and espresso powder. Bring to the boil while stirring and simmer for about 1 minute. Remove from heat. Whisk the egg yolks and 4 tbsp. milk. Stir 2 tbsp. pudding into the egg milk, then stir everything into the rest of the pudding.
Put chocolate on the hot pudding, let it melt and stir in. Fold in the beaten egg white. Dust the pudding with cocoa. Whipped cream tastes good with it.