Vietnamese cinnamon is available online and in most specialty shops. It has a zestier flavor, similar to Red Hots. You can substitute with cinnamon, for a total of 2¼ teaspoons.
If using pre-ground nutmeg, reduce the quantity by half.
In my opinion, this bread tastes best 2 to 3 days after it’s made, and will last for up to 5 days.