Add banana to a microwave safe bowl and mash it with a fork.
Add the rest of the ingredients to the bowl. Mix well.
Add enough water to cover the oats. Mix again.
If using rolled oats, microwave for 1 minute, stir, and then microwave for another minute. Stir again. Microwave for another 30 seconds. If using quick oats, microwave for 1 minute, stir and then microwave for another 30 seconds - 1 minute.
While the oats are cooking, make the whey drip. Add the protein powder and optional peanut butter powder to a small bowl. Add a tiny bit of water at a time, stirring until well combined, until it reaches a thick, frosting-like consistency.
Add frozen berries to the top of the cooked oats while still warm. Pour the whey drip over the oats/berries. Enjoy!