Step 1: Prepare Cornstarch Mixture

Place 1 cup of the milk into saucepan. Add lemon peel and cinnamon sticks . Bring milk to a simmer over medium heat . Meanwhile , in a small bowl, Whisk together the cornstarch and sugar

Step 2: Prepare and Serve Blanc Mange

Whisk remaining milk into the cornstarch mixture, when the milk in the pan begins to simmer, pour the cornstarch mixture into the saucepan in a thin steady stream . Whisk vigorously and increase heat just a bit to bring the mixture to a gentle boil. Allow the mixture to boil for 20 seconds while continuing to whisk, then remove from the heat . Remove the lemon peel and cinnamon sticks . Stir in the pinch of cinnamon and , if using, the vanilla. Pour into a disk or mold , and refrigerate for at least 6 hours, or overnight . Garnish with shaved chocolate just before serving .