Preheat your oven to 350”F. In a bowl combine the nuts, cinnamon and half of the orange zest, set aside. Brush a 9x13 inch oven proof dish with some of the butter.
Cut the fillo dough sheets in half and start layering 10 of them in the bottom of the pan, one by one, brushing each one with some of the melted better before topping with another. Sprinkle with a quarter of the nuts all over. Top with 4 more fillo sheets brushing them with melted butter in between. Sprinkle another quarter of the nuts and layer another 4 fillo sheets on top. Sprinkle with another quarter of the nuts and 4 more fillo dough sheets. Top with the rest of the nuts and the remaining 10 layers of fillo sheets, making sure you brush each one of them with butter in between. Using a sharp knife cut the Baklava into 2 inch strips, then slightly angled horizontal cuts to create a diamond pattern. Or just do squares or whatever shape you like, only make sure to do it before baking it.
Bake the Baklava in the preheated oven for 1 hour until golden brown on top.
Meanwhile make the the honey orange syrup by whisking together the orange juice, lemon juice, honey and the remaining orange zest. Pour it all over the Baklava once it comes out of the oven. Allow it to sit at room temperature for a few hours or overnight for the baklava to soak it all up.
To melt the chocolate, break it into small pieces and place it in the top pan of a double boiler over hot water. Stir until nicely melted and using a spoon drizzle some all over the Baklava. Garnish with the crushed pistachios and sea salt flakes and enjoy !
Make sure to keep the fillo dough moist with a wet tea towel while assembling the Baklava.