Preheat your oven to 350�F (175�C) and grease a baking dish with melted butter.
Thaw the phyllo dough according to the package instructions, and cover it with a damp cloth to prevent it from drying out.
In a mixing bowl, combine the finely chopped nuts with cinnamon if using.
Brush the bottom of the baking dish with melted butter. Place a sheet of phyllo dough in the dish and brush it with more butter. Repeat this process, layering about 10 sheets of phyllo dough, brushing each sheet with butter.
Spread a layer of the nut mixture evenly over the buttered phyllo dough.
Continue layering phyllo dough and butter, adding another 10 sheets on top of the nut mixture, brushing each sheet with butter.
Using a sharp knife, carefully cut the baklava into desired shapes, such as squares or diamonds.
Bake the baklava in the preheated oven for 40-50 minutes, or until golden brown and crisp.
While the baklava is baking, prepare the syrup. In a saucepan, combine the granulated sugar, water, honey, and lemon juice. Bring the mixture to a boil, then reduce the heat and simmer for about 10 minutes, until slightly thickened.
Once the baklava is done baking, remove it from the oven and immediately pour the hot syrup over the hot baklava, ensuring that it is evenly distributed.
Allow the baklava to cool completely in the baking dish, allowing it to absorb the syrup and develop its flavors.
Once cooled, carefully lift out the individual pieces of baklava and serve. Optionally, garnish with additional nuts on top.