Spray a 9x13 pan with cooking spray and set aside.
In a large bowl, combine oats, cinnamon, baking soda, salt, and walnuts. Toss until well combined.
In a separate bowl, mash bananas and stir in eggs, maple syrup, vanilla, and almond milk.
Pour wet ingredients into the bowl of dry ingredients and stir to combine until all oats are coated.
Pour oat mixture into 9x13” pan. Top with additional walnuts and sprinkle with cinnamon if desired.
Bake for 30 minutes and serve warm.
Notes
If your family doesn't finish this in one sitting, these leftovers can easily be stored in the fridge for up to four days. Just reheat it in the microwave for a quick breakfast!