In a saucepan bring the water with the cinnamon sticks to a boil. Remove from heat, cover, and let steep for 1 hour. Discard the cinnamon sticks.
Add salt and oats to the water and let it come to a boil uncovered. Lower heat and simmer for 30 minutes, stirring frequently to prevent sticking. Add milk and simmer for an additional 15 minutes until creamy.
Serve in a bowl and add more milk or water if you want it thinner. Sprinkle with cinnamon and sweeten with sugar or honey. Serve garnished with blueberries and walnuts.
When you puree it in the blender it becomes an atole, smooth oatmeal, which is a good way to prepare it for the elderly and the very young.
If you are lactose intolerant, use lactose-free milk. Or substitute regular milk for a vegan version like oat, almond, or soy milk.