Prepare the Base: In a jar or bowl, combine rolled oats, almond milk, chia seeds (if using), vanilla extract, and honey or maple syrup. Stir well to combine.
Layer the Goodness: Gently fold in sliced banana and chopped walnuts.
Store Overnight: Cover the jar or bowl with a lid or plastic wrap and refrigerate overnight.
Serve: In the morning, stir the oats and enjoy! Top with additional banana slices, walnuts, yogurt, or any toppings of your choice.