In a 16 ounce mason jar or two 8 ounce jars, combine all the ingredients for the oats base. Stir everything together until it’s all combined.
Place the jar(s) in the refrigerator and let the mixture sit overnight (or for at least 2 hours) to allow the oats to thicken and soften.
Either the night before or in the morning, prepare the caramelized bananas. To do so, toss sliced bananas with coconut sugar and cinnamon in a bowl.
Heat coconut oil in a large skillet over medium-high heat. Once the oil is hot, add the bananas in a single layer. Let the bananas cook for about 4 minutes on one side until they start to turn golden brown. Then, carefully flip and cook for another 4 minutes.
Spoon the caramelized bananas on top of the oats. Then, top with walnuts, peanut butter, and cinnamon, if desired.