In a medium-sized jar or bowl, add rolled oats, creamy peanut butter, protein powder, chia seeds, and your choice of milk. Use a whisk or spoon to blend all the ingredients together thoroughly, ensuring there are no clumps.

Assess the consistency of the mixture. If it appears too thick, add a splash more milk until you reach your desired creaminess.

Cover your jar or bowl with a lid or plastic wrap to seal in freshness. Place it in the refrigerator and allow it to chill overnight for at least 4 hours.

The next morning, retrieve your oats from the fridge. Give them a good stir to mix any liquid that may have settled. If too thick, add a bit more milk and stir again before serving.