Let the dough sheets rest at room temperature for about 10 minutes. Melt butter. Cut dough sheets in half. Grease an ovenproof dish (20 x 30 cm) thinly with butter. Place 15 layers of filo pastry on top of each other, spreading each layer thinly with butter and using the entire surface of the mould. (Place the individual sheets of dough alternately on the left or right edge of the mould so that the entire mould is filled).
Finely chop the pistachios in the universal chopper and, except for 2 tbsp. for sprinkling, mix with sesame seeds and spread on the dough. Place the remaining sheets of dough on top and spread with the remaining butter. Cut into rectangles of approx. 3 x 4 cm with a sharp knife. Pour the rest of the butter on top
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 45 minutes until golden brown. Cover with aluminium foil after approx. 15 minutes
Bring the sugar, lemon juice and 300 ml water to the boil and boil down over a low heat for about 20 minutes to form a syrup
Take the baklava out of the oven and pour the hot syrup over it. Let it cool down. Sprinkle the baklava with the remaining pistachios before serving