1. Preheat oven to 175 degrees C or 350 degrees F.
2. In a large mixing bowl, put cooked rice, milk, caster sugar, and egg.
3. Add vanilla, and cinnamon to it. Mix well.
4. In a non stick baking dish, pour the mixture.
5. Pop it in oven and bake for 25-30 minutes.
6. Remove from oven, and allow it to cool for 5 minutes.
7. Then, put it in refrigerator for about 3 hours.
8. Sprinkle cinnamon and serve it immediately.
Add more rice if you find your mixture is too watery.