For the Syrup:
1 cup sugar
1 cup honey
3/4 cup water
1 tablespoon lemon juice
2 cinnamon sticks
1 (1-inch) strip lemon zest
2 pinches ground cloves
2 pinches ground cardamom
Filling and Dough:
1 pound walnuts, or a combination of walnuts, pistachios, and almonds
1 1/2 teaspoons ground cinnamon
1/4 teaspoon salt
2 sticks unsalted butter
1 pound phyllo, thawed according to package instructions
To make the syrup: Combine the sugar, honey, water, lemon juice, cinnamon sticks, lemon zest, cloves, and cardamom in a medium saucepan. Cook over medium heat, stirring occasionally, until the sugar is dissolved. Reduce the heat to medium-low and cook until the syrup is slightly thickened, about 10 minutes. Remove the cinnamon sticks and lemon zest and set aside to cool.
To make the filling and dough: Using a sharp knife or food processor, finely chop the nuts. In a mixing bowl, combine the nuts, cinnamon, and salt and stir well to combine.
Melt the butter over low heat in a small saucepan.
Using a pastry brush, lightly coat a 9-by-13-inch or 10-by-15-inch baking dish with some of the melted butter.
Open the package of phyllo and lay the thin sheets on a clean work surface next to your baking dish; if the sheets measure approximately the same size, then proceed from here. If they are larger, use a sharp knife to cut the phyllo sheets approximately the same size as your baking dish. Discard any scraps. Cover the sheets with a piece of plastic wrap or a lightly damp kitchen towel; the sheets of phyllo dry out very quickly if left uncovered.
Preheat the oven to 350º F.
Place one of the sheets of phyllo in the bottom of the buttered baking dish and lightly brush with some of the melted butter. Repeat this procedure with 6 more sheets of phyllo, for a total of 7 layers. Spread 3/4 cup of the nut mixture evenly over the buttered phyllo sheets. Repeat again with 7 more sheets of phyllo, buttering each layer as before, and top these sheets with another 3/4 cup of the nut mixture. Continue this layering process, buttering 7 sheets of phyllo and topping each 7 sheets with 3/4 cup of the nuts, until you have used all of the nut mixture. Layer any remaining sheets of phyllo on top, buttering between each layer, until all of the phyllo sheets have been used.
Use a sharp knife to make four lengthwise cuts through the layered phyllo at 1 1/2-inch increments. You should have 5 (1 1/2-inch) wide strips lengthwise. Then cut diagonally at 1 1/2-inch increments to form diamond shapes. You should end up with approximately 36 diamond-shaped pieces of baklava.
Bake the baklava until golden brown, about 40 minutes.
Remove from the oven, set aside on a wire rack to cool 5 minutes. Using a ladle or small measuring cup, drizzle the cooled syrup over the warm baklava. Allow to stand several hours before serving.