In a blender, add the frozen mixed berries, grapes, orange juice and peanut butter.
Blend until smooth. Taste the smoothie and adjust any ingredients you may want more of, like peanut butter.
Pour the smoothie into glasses and enjoy.
Notes
Feel free to add in the protein powder of your choice to get more protein in.
Consider adding a banana or some fresh spinach to add more nutrition to the smoothie.
You can substitute the orange juice for the dairy or non-dairy milk of your choice for a slightly different flavor profile.
Place leftovers into a covered container and refrigerate for up to 3 days. We highly recommend blending it one more time before enjoying your smoothie to get all the ingredients re-mixed.