Peel and mash the banana in a medium-sized mixing bowl.
Add the oats, egg white, almond milk, and cinnamon to the bowl with the banana and mix everything together until everything is thoroughly combined. Make sure there is room at the top of the bowl so that the oats have space to expand in the microwave.
Microwave the mixture on high for 3 minutes, stirring after 75 seconds and then again every 30 to 45 seconds until 3 minutes are up.
Enjoy as-is or top with your favourite toppings and enjoy immediately.
Notes:
Topping options
Natural peanut butter, chopped almonds, fresh berries, and pumpkin pie spice.