Add all ingredients to a blender: frozen banana, Greek yogurt, almond milk, peanut butter, oats, vanilla extract, and protein powder.
Blend until smooth and creamy.
Notes
If using sweetened protein powder, taste the smoothie first before adding maple syrup.
This smoothie is best enjoyed right away. However, if needed, you can store it in an airtight container in the refrigerator for up to 24 hours. Give it a good stir before drinking, as the ingredients may separate.
To make this smoothie ahead of time, blend it the night before and store it in the fridge or prep the ingredients (minus the milk and yogurt) in a freezer bag to blend later on.
Nutrition Disclaimer: Nutrition was calculated with a general protein powder which has 25 grams per scoop. Yours may be slightly different!