Preheat the oven to 180° C and roast hazelnuts for about 10 minutes, use Your fingers to remove the skin of hazelnuts when they are completely cool. Leave several whole nuts to put inside the truffles and chop the others.

Crush wafers, add hazelnuts, Nutella and mix until well combined. Shape the mix into small balls adding one hazelnut in the center. It is easier to form balls when hands are wet. Refrigerate all balls for at least 1 hour.

Melt the chocolate with oil. Cover chilled balls with chocolate and refrigerate until they harden.