To open the frozen pouch of acai puree, run it under warm water for 10 seconds. You should feel the puree loosen enough to break it up into chunks and will easily be able to open the bag with scissors.
In a high-speed blender, combine the acai puree, dates, orange juice, water, frozen mango, and spinach and blend until completely smooth.
If you'd like a thicker shake, feel free to add a handful of ice cubes and blend again until your desired texture is achieved. Serve immediately.