In a medium-sized pot, bring the water and coconut milk to a boil. Add in steel-cut oats and a pinch of salt and reduce heat to low.
Stir in the mashed banana (mashing it helps disperse the sweetness throughout), ground flax, and chia seeds. Simmer on low, uncovered, for 20-25 minutes, stirring every 5 mins or so.
When the oats are creamy and tender, remove from heat and stir in cinnamon to taste and pure vanilla extract. Serve immediately or allow to cool before transferring into air tight containers in the fridge. In the morning, add a splash of coconut milk and reheat on the stove-top. Mix in Cinnamon Sunbutter spread and top with bananas, strawberries, or favorite fruits!