(Optional) If you would like to remove the skin from the hazelnuts roast them for 5 minutes at 200ºC (400ºF) or just enough to dry the skin. Place the hazelnuts on the clean kitchen towel, close tightly, rub between your hands for a minute or so. The skins should come off easily. Be careful not to overbake the hazelnuts. They should not take on the color.
Process the hazelnuts, cardamom, ginger, and cinnamon in the food processor until very fine. Place in a clean bowl and set aside. (Note 1)
Process the dates, prunes, golden raisins, vanilla paste, lemon zest, and juice in the food processor until it resembles a sort of a dough-like structure. (Note 2)
Add the hazelnuts to the food processor and pulse until the mass is cohesive.
Transfer to the parchment paper and pat it tightly into a square about 1cm (½in) thick. Place in the fridge to cool completely.
Cut into either squares or rectangles or any other shape you wish.
Wrap each bar in the parchment paper so that they don't stick to each other. Place them in a sealed glass container and either keep them in the fridge or on the counter.
NOTES
Make sure not to overprocess the hazelnuts so that they start releasing the oils and turn slowly into butter. They should have a consistency of coarse nut flour.
Once processes it should cling into a bowl, like pasta dough.