In a medium pan, bring water, milk, star of anise, cardamom pods, chai seasoning and tea bags to a boil. Once it comes to a boil, reduce the heat and let simmer for 3-4 minutes. Make sure you stir constantly because you don't want the milk to burn to the bottom of the pan. Remove the tea bags, star of anise and cardamom pods. Then, stir in oats. Cook until thick, about 5-7 minutes. Stir in vanilla extract and serve.