Make the syrup first so it has time to cool completely. Combine the 1 cup water, ¼ cup granulated sugar, ½ cup honey good quality, 1 tbsp fresh lemon juice, and 1 tsp ground cinnamon in a small Saucepan over medium heat. Stir until the ¼ cup granulated sugar dissolves, then bring to a gentle boil. Reduce heat and simmer for 10 minutes without stirring, until slightly thickened. Remove from heat, stir in the 1 tsp pure vanilla extract and 1 cup water (if using), and discard the 1 tsp ground cinnamon. Let the syrup cool to room temperature — this is critical for crispy baklava.

Add the 2 cups walnuts roughly chopped and 1 cup pistachios shelled, roughly chopped to a Food Processor and pulse 8–10 times until coarsely chopped — you want small pieces with some texture, not a fine powder. Transfer to a Mixing Bowl and stir in the ¼ cup granulated sugar, 1 tsp ground cinnamon, ⅛ tsp ground cardamom (if using). Set aside.

Preheat your Oven to 350°F. Melt the 1 ½ cups unsalted butter clarified or melted and skimmed in a small Saucepan or Microwave and keep it warm. Brush the bottom and sides of a Baking Dish generously with melted 1 ½ cups unsalted butter clarified or melted and skimmed.

Unroll the 1 lb phyllo dough thawed overnight in the Refrigerator and lay it flat. Keep the stack covered with a slightly damp kitchen towel at all times to prevent it from drying out — 1 lb phyllo dough thawed overnight in the refrigerator dries quickly and becomes brittle. Trim the 1 lb phyllo dough thawed overnight in the refrigerator sheets to fit your pan if needed.

Layer 8–10 sheets of 1 lb phyllo dough thawed overnight in the refrigerator into the buttered Baking Dish, brushing each sheet generously with melted 1 ½ cups unsalted butter clarified or melted and skimmed before adding the next. Don't skip any sheets — every layer needs 1 ½ cups unsalted butter clarified or melted and skimmed for the pastry to crisp and separate properly.

Spread one-third of the nut filling evenly over the buttered 1 lb phyllo dough thawed overnight in the Refrigerator base. Then layer 4–5 more 1 lb phyllo dough thawed overnight in the refrigerator sheets on top, brushing each one with 1 ½ cups unsalted butter clarified or melted and skimmed. Repeat this process — one-third of the nuts, then 4–5 buttered 1 lb phyllo dough thawed overnight in the refrigerator sheets — two more times. Finish with a top layer of 8–10 buttered 1 lb phyllo dough thawed overnight in the refrigerator sheets, making sure the very top sheet is well-coated with 1 ½ cups unsalted butter clarified or melted and skimmed.

Using a very sharp Knife, cut the baklava all the way through to the bottom of the pan in a diamond or square pattern. Diamonds are traditional: make parallel cuts diagonally across the pan about 1.5 inches apart, then cut straight lines across to form diamond shapes. Cutting before baking is essential — 1 lb phyllo dough thawed overnight in the refrigerator shatters if you try to cut it after baking.

Bake on the center rack at 350°F for 40–45 minutes, until the baklava is deeply golden brown on top. Check at the 30-minute mark — if the top is browning too fast, tent loosely with Aluminum Foil for the remaining time.

Remove the baklava from the Oven and immediately pour the cooled syrup slowly and evenly all over the hot baklava. You will hear a satisfying sizzle. Pour it over all the cut lines so the syrup soaks into every layer. Do not cover the pan.

Let the baklava rest uncovered at room temperature for at least 1 hour — ideally 4 hours or overnight — so the syrup is fully absorbed and the layers set. Sprinkle with finely chopped 1 cup pistachios shelled, roughly chopped for garnish if desired. Serve at room temperature directly from the pan.