Preheat the oven to 350°F (175°C).
In a bowl, combine the chopped walnuts, almonds, pistachios, sugar, cinnamon, and cloves. Mix well.
Brush a baking dish with melted butter.
Place a sheet of phyllo dough in the baking dish and brush it with melted butter. Repeat the process with half of the phyllo sheets.
Spread the nut mixture evenly over the phyllo sheets in the baking dish.
Layer the remaining phyllo sheets on top of the nut mixture, brushing each sheet with melted butter.
Using a sharp knife, cut the baklava into diamond or square shapes.
Bake in the preheated oven for 45-50 minutes, or until golden brown and crisp.
While the baklava is baking, prepare the honey syrup. In a saucepan, combine the water, honey, lemon juice, and vanilla extract. Bring to a boil and simmer for 5 minutes.
Remove the baklava from the oven and immediately pour the hot honey syrup over it. Let it cool completely before serving.