1. Combine chocolate, orange peel, cinnamon and 3 tablespoons of milk in a saucepan and heat very gently until chocolate melts, stirring frequently.
2. Add remaining milk and heat through gently until piping hot, stirring frequently. Whisk whipping cream until soft peaks form.
3. Pour hot chocolate into mugs or heatproof glasses. Top with whipped cream.Sprinkle with grated chocolate and add a cinnamon stick to each one for stirring.
4. Wind a curly strip of orange peel around cinnamon sticks for a pretty effect, if desired.