Add oats, water, and milk into a medium sized saucepan and bring to a simmer on high heat, stirring occasionally.
When the mixture comes to a simmer, reduce to a medium heat, and allow it to continue to simmer until the mixture thickens (about 15 to 20 minutes), stirring occasionally.
Take the mixture off the heat and serve in bowls. Allow to sit for a couple of minutes before adding any desired toppings.