Add oats, cinnamon, vanilla, sea salt, and half of the banana slices to a medium pot.
Pour in water and stir to combine.
Cook over medium-high heat for 8–10 minutes, stirring occasionally until the oats are thick and creamy. The banana should melt into the mixture.
While cooking, heat a skillet over medium heat and add coconut oil and maple syrup.
Add remaining banana slices and walnuts. Cook for about 2 minutes per side until golden and caramelized.
Transfer the cooked Banana Bread Oatmeal to a bowl and top with caramelized bananas and walnuts.
Drizzle extra maple syrup if desired and serve warm.