Place cashews in a blender/coffee grinder and blend until it forms a fine flour consistency.
Pour into a mixing bowl and mix all ingredients together (for the base).
Place in a lined brownie tin, and bake at 180°c for 10-12 mins until golden on the edges. Set aside to cool.
Place layer of nut butter on top of the base and place in freezer for 10 mins. Take out and place chocolate layer on top and place in fridge to allow to set for roughly 2 hours.