Slice vanilla beans
in half. In a saucepan bring milk, cream, cinnamon sticks
, vanilla beans, and zests to a simmer
for a few minutes. Discard cinnamon and vanilla beans.
In a bowl whisk
yolks together with the cornstarch
and 2 cups sugar until incorporated and creamy. Slowly add this mixture into the saucepan
of warm milk
, mixing continuously.
Slowly heat the mixture over low heat, stirring the entire time, until it begins to thicken. Make sure that it does not boil. Pour into 12 shallow serving dishes, cool to room temperature, and refrigerate for several hours.
To serve sprinkle cold custards with the remaining sugar and caramelize
with a torch or under a hot broiler.