Place the frozen banana in the blender and add the rest of the ingredients. Blend until smooth. I only add just enough milk to cover the bananas. That way it maintains a silky thick texture. Using any type of coconut or almond milk would work well with this recipe. I prefer dairy free milks that contain coconut. I find it provides a rich creamy component.
If you want to make this more like a creamy milkshake, add one to two tablespoons of canned coconut cream.