Preheat oven to 160c/gas mark 3
Place all of the filling ingredients in to a large bowl and mix together
Roll out the pastry to a thickness of approximately 5-6mm and line the tins with it.
Place parchment paper on to the pastry lining the tins and weigh down evenly with the baking beans / pie weights.
Blind bake the pastry in the oven for 10-15 mins depending on how hot your oven is. Blind baking stops the bottom of the pie going soggy.
Remove the pie weights and parchment paper from the pie crust and fill the pies evenly with the filling from the bowl.
Put back in to the oven and bake for a further 10-15 mins or until a skewer comes out of the centre of the pie clean.
Allow to cool and then pipe around the edges of each pie with the Nutella and sprinkle with the chopped hazelnuts.