Roast pistachios and walnuts in a pan without fat. Take them out and let them cool down. Let the dough rest in the pack at room temperature for about 10 minutes. Melt butter. Spread a rectangular ovenproof dish (approx. 25 x 20 cm) with some melted butter.
Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Break dark chocolate into pieces for the filling. With roasted nuts, 2 tablespoons of sugar, 1⁄2 TL cinnamon and orange zest finely grind in the universal chopper.
Roll out the dough sheets. Place 3 sheets on top of each other, brushing each thinly with melted butter (1 sheet of dough is not needed). Spread the filling on each of the 3 pastry sheets thus created, leaving an approx. 3 cm wide edge on the long sides.
Roll up from one long side at a time. Carefully cut each roll into 8 pieces with a sharp knife and place them close together in the greased form. Rest
Bake in a hot oven for 20-25 minutes until golden brown and crispy.
Meanwhile, for the orange syrup, heat 160 g sugar, honey, orange juice and 160 ml water in a pot at low heat and stir until the sugar has dissolved. Bring to the boil and boil down over low heat for about 15 minutes.
Take the baklava out of the oven and pour the hot syrup over it. Let it cool down for at least 3 hours.