1 lb pistachios or walnuts (or a mix of both), coarsely ground
1/2 t ground cinnamon
1 c zwieback crackers or breadcrumbs
4 sticks unsalted butter, melted
16 sheets phyllo dough (thawed, if frozen), cut in half
3 c sugar
1 1/2 c water
8 oz honey
1 T fresh lemon juice
Position a rack in the lower third of the oven; preheat to 350 degrees F. Combine the nuts, cinnamon and ground crackers in a bowl.
Brush a 9-by-13-inch baking dish with some of the butter. Layer 10 pieces of phyllo in the dish, brushing each piece with butter before adding the next (keep the remaining dough covered with a damp towel). Sprinkle a quarter of the nut mixture over the dough. Layer 4 pieces of phyllo on top, brushing each with butter before adding the next; sprinkle with another quarter of the nut mixture. Add 4 more phyllo pieces on top, brushing each with butter, then add another quarter of the nut mixture, 4 more pieces of phyllo with butter, and the remaining nuts.
Layer the remaining 10 pieces of phyllo on top of the nuts, brushing each with butter; brush the top piece with extra butter. Cut into the baklava to make strips, about 1 1/2 inches wide. Then make diagonal slices, about 1 1/2 inches apart, to create a diamond pattern. Bake until golden, about 1 hour.
Meanwhile, make the syrup: Bring the sugar, honey and 1 1/2 cups water to a boil in a saucepan over medium heat and cook, 10 to 15 minutes. Add the lemon juice and boil 2 more minutes, then let cool slightly.
Pour the syrup over the warm baklava; let soak, uncovered, at least 6 hours or overnight. Garnish with nuts.