01 - Preheat oven to 350°F. Generously grease a 9x13 inch baking dish with melted butter.
02 - Combine chopped walnuts, pistachios, almonds, sugar, and cinnamon in a large bowl. Mix thoroughly to distribute spices evenly.
03 - Unroll phyllo dough and keep covered with a damp kitchen towel to prevent drying out while working.
04 - Layer 8 sheets of phyllo in the prepared dish, brushing each sheet generously with melted butter before adding the next.
05 - Sprinkle approximately one-third of the nut mixture evenly over the phyllo base.
06 - Add 4 more sheets of phyllo, brushing each with butter. Spread half of the remaining nuts over the surface.
07 - Place 4 additional phyllo sheets, buttering each one. Sprinkle the final layer of nuts evenly across the dough.
08 - Finish with remaining phyllo sheets, brushing each layer with butter as you assemble.
09 - Using a sharp knife, cut the baklava completely through into diamond or square shapes before baking.
10 - Bake for 35-40 minutes until the pastry turns deep golden brown and appears crisp throughout.
11 - While baklava bakes, combine water, sugar, lemon juice, honey, cinnamon stick, and orange peel in a saucepan. Bring to a boil, then reduce heat and simmer for 10 minutes. Remove cinnamon and peel; let syrup cool slightly.
12 - Immediately pour warm syrup over the hot baklava as soon as it comes out of the oven. Allow to cool completely for several hours so pastry absorbs syrup fully before serving.