A green goddess (or monster!) smoothie

This smoothie looks frankly terrifying as its dark green, but it's extremely good for you and you can't taste the 'green' taste. In fact it tastes a bit like a non alcoholic mojito

Place the following ingredients in a blender
Serves 1
- a handful of mixed berries
- a couple of sprigs of mint
- a chunk of cucumber about 3 inches long
- a teaspoon of spirulina powder (you can buy this in health food shops or substitute with a handful of spinach leaves of just leave it out)
- juice of half a lime
- an egg white (optional if you want to up the protein, read why here)
Blend all of the ingredients until smooth, you could blend with ice if it was a warm day, and serve.