01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan with melted butter.
02 - Combine walnuts, almonds, pistachios (if using), sugar, cinnamon, and cloves in a bowl. Mix thoroughly for even distribution.
03 - Place one phyllo sheet in the pan. Brush lightly with melted butter. Repeat, layering and buttering 6-8 sheets to create the foundation.
04 - Sprinkle one-third of the nut mixture evenly across the buttered phyllo sheets.
05 - Layer and butter 4-5 more phyllo sheets. Add another one-third of the nut mixture, spreading uniformly.
06 - Add another 4-5 buttered phyllo sheets, then distribute the remaining one-third of nut mixture.
07 - Finish with remaining phyllo sheets, brushing each with butter including the final top layer.
08 - Using a sharp knife, cut baklava into diamond or square shapes before baking to ensure clean cuts.
09 - Bake 35-40 minutes until phyllo turns golden brown and becomes crisp throughout.
10 - While baklava bakes, combine sugar, water, and lemon juice in a saucepan. Boil 8-10 minutes until slightly thickened. Remove from heat, stir in honey and rose water or orange blossom water if using.
11 - Pour hot syrup evenly over hot baklava immediately after removing from oven. Allow to cool completely so pastry fully absorbs the syrup before serving.