Set aside 4-5 tablespoons milk. Heat the remaining milk with the chopped chocolate, orange zest and halved vanilla bean pod. Separate the eggs and beat the egg whites with the salt until stiff. Whisk the egg yolks and sugar until foamy then stir in the cornstarch and reserved milk.
Bring the chocolate milk to a boil.
Slowly whisk the hot milk into the egg yolk mixture, remove the vanilla bean pod, return to the saucepan and gently heat until thickened. Fold in the egg whites.
Fill the serving glasses with pudding, let cool then chill in the refrigerator.
Garnish with edible flower petals, if desired.