In a fry-pan on medium low heat, sweat off shallot and garlic until tender. Then add Cavolo Nero cook for another couple of minutes or until the kale is wilted.
Transfer into a medium mixing bowl and set aside to cool slightly.
Add the cheeses, stir through and season with the salt, pepper and nutmeg.
Place 1 sheet of pastry on lined tray. Top with the cheese mixture, leaving enough edge to seal the pastry pastry. Using a pastry brush, eggwash edges and then add the top layer of pastry. Crimp the edges together decoratively with a fork.
Bake in the oven for 25-30 minutes, or until pastry is golden brown.