Place mango into a blender with milk or water and blend until smooth, adding more mango to thicken and more water or milk to thin.
Pour 2/3 of the smoothie into a serving container and then add strawberries to the blender. Blend until smooth, adding a bit more water or almond milk if needed. Taste to see if it needs to be sweetened. I added 1/2 a small frozen banana at this point.
Pour 3/4 of the smoothie into the serving glass on top of the mango layer.
Lastly, add spinach to the blender and blend until smooth. Pour into the serving glass, making three distinct layers.
Sip and enjoy, or freeze for later.
*Nutrition information is a rough estimate calculated without sweetener.