Remove stems from strawberries. Using a small vegetable knife, cut out centres and pipe Nutella into strawberries.
Insert a toothpick into the side of each strawberry. Holding toothpick, quickly dip stem end of strawberry into melted chocolate. Allow the excess chocolate to drip off.
Sprinkle with hazelnuts and place strawberries on a grease proof paper-lined baking sheet, point side up.
Remove the toothpicks and refrigerate the strawberries until set. Just before serving, dust with icing sugar.