To make the crust, process the oats into flour in a blender or food processor. If using a food processor, add the dates and process until it all begins to stick together. Press the "dough" into the bottom of a springform pan or adjustable pan. Put in the fridge.
To make the creme: blend everything together - except the blueberries - until smooth and creamy; like thick yogurt.
Pour half of this mixture onto your crust, then sprinkle on 1 cup of blueberries. Add the remaining blueberries to the mixture still in your blender, and blend until smooth. Pour this on top of your first layer and blueberries.
Put in the fridge overnight, then decorate with whatever you like, slice, and enjoy!