01 - Preheat oven to 350°F. Generously grease a 9x13-inch baking pan with melted butter.
02 - Combine walnuts, almonds, pistachios if using, sugar, cinnamon, and cloves in a mixing bowl. Stir until evenly blended.
03 - Place one phyllo sheet in prepared pan. Brush lightly with melted butter. Repeat layering and buttering 6–8 sheets total.
04 - Sprinkle one-third of nut mixture evenly across buttered phyllo sheets.
05 - Layer and butter 4–5 additional phyllo sheets. Spread second one-third of nut mixture over dough.
06 - Add another 4–5 buttered phyllo sheets. Top with remaining nut mixture.
07 - Layer remaining phyllo sheets, brushing each with melted butter including the final top sheet.
08 - Using a sharp knife, cut completely through layers into diamond or square shapes.
09 - Bake 35–40 minutes until pastry turns golden brown and crisp throughout.
10 - While baklava bakes, combine sugar, water, and lemon juice in saucepan. Boil 8–10 minutes until sugar dissolves completely.
11 - Remove from heat. Stir in honey and rose water or orange blossom water if using.
12 - Immediately pour hot syrup evenly over hot baked baklava. Allow to cool completely at room temperature so syrup fully absorbs before serving.