Add all of your ingredients to your blender. You want to use a very ripe banana because they do a better job of sweetening your smoothie without needing any additional sweeteners. If it isn't sweet enough for you, though, you can add whatever sweetener you prefer.
Blend all of your ingredients together. You can add in a little water and/or ice to get the consistency you prefer. The ice will thicken it a bit and make it colder, of course.
You can optionally add in a raw, pastured egg or some protein powder.