Position a rack in the lower third of the oven and preheat to 350 degrees. Cut 16 sheets of thawed phyllo dough in half and cover with a damp towel until needed. Coarsely grind 1 pound of pistachios or walnuts, or a mixture, and combine in a bowl with 1/2 a teaspoon of ground cinnamon and 1 cup of ground zwieback crackers or breadcrumbs.
Melt 4 sticks of unsalted butter and use some to grease a 9-by-13-inch baking dish. Place 10 sheets of phyllo in the dish, brushing each layer with butter as you go. Sprinkle over a quarter of the nut mixture, then add 4 further layers of phyllo, brushing each with butter. Continue in this manner until all the nuts are used up. Layer 10 remaining sheets on top, buttering each one.
Cut the baklava into strips about 1 1/2 inches wide, then make a diamond pattern by slicing diagonally every 1 1/2 inches or so. Bake in the oven for about 1 hour, or until golden.
Make a syrup by boiling 3 cups of sugar, 8 ounces of honey and 1 1/2 cups of water in a saucepan over medium heat. Cook for 10 to 15 minutes, add 1 to 2 tablespoons of fresh lemon juice and boil for 2 minutes. Cool slightly before pouring over the warm baklava. Allow to soak, uncovered, for at least 6 hours. Garnish with ground nuts.Learn more about Cooking