Peel and chop the banana. Place it in a screw-top jar along with the rolled oats, chia seeds, protein powder, and peanut butter.

Pour milk over the oat mixture and stir thoroughly until no lumps remain.

Cover the overnight oats jar or bowl and refrigerate overnight (and for up to four days).

Serve overnight oats the next morning, either cold or warm, with your choice of fresh fruit. For warm overnight oats, microwave the jar at 800 watts for approximately 90 seconds. Please keep an eye on the oats, as microwaves vary and they can boil over. Also, make sure you use a microwave-safe container.