Blend the walnuts in a food processor into a fine meal but be careful not to over process into a nut butter at this stage. Put aside half a cup of the walnut meal for rolling the balls in at the end.
Add the dates and process together until they have been chopped up and the mix has formed a crumbly texture. Add remaining ingredients and blend until it forms a smooth and sticky paste. Shape each ball into the size of a large cherry tomato and roll in walnut meal. Chill in the fridge for 1 hour or overnight for a firm fudge-like texture.