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Recipe adapted from Ghaya Oliveira, Boulud Sud, New York City
Yield: Approximately 80 pieces
Cook Time: 1 hour, plus 1 day rest
1¾ cups Sicilian pistachios, coarsely ground in a food processor
2 cups pistachio powder
22 sheets phyllo dough
1¼ cups clarified butter, melted
5 cups water
7½ cups granulated sugar
Juice of 1 medium lemon
1 tablespoon all-purpose flour, sifted
1. Preheat the oven to 350°F.
2. In a medium bowl, combine the ground pistachios with the pistachio powder.
3. Trim the sheets of phyllo so they're just a bit larger than a 13-by-9-by-2-inch baking sheet and keep them covered with a damp cloth during the assembly process. Brush the bottom and sides of the baking sheet with butter. Lay one sheet of phyllo on the baking sheet and brush with clarified butter. Cover that piece of phyllo with a second piece and brush with more clarified butter. Repeat this step 9 more times so that there area total of 11 sheets of phyllo. Trim the phyllo to keep the edges neat.
4. Top the first sheet of phyllo evenly with the nut mixture. With the remaining phyllo sheets, repeat the phyllo layering detailed in Step 3 so that a second 11-layer stack of phyllo sits on top of the nut mixture.
5. Using a sharp knife, cut a 1-inch diamond crosshatch pattern, making sure to cut through all the layer of the phyllo. Brush the top generously with butter.
6. Place the baklava in the oven and bake until golden brown, about 30 to 40 minutes. Remove from the oven and set aside to cool for 20 minutes.
7. Meanwhile, combine the water, sugar and lemon juice in a small saucepot placed over medium-high heat. Bring to a simmer; remove the pot from the heat when the syrup reaches 236° (soft-ball stage) on a candy thermometer, about 10 minutes. Use a spoon to remove any film that rises to the surface. Remove the pot from the heat and whisk in the flour.
8. Using a sharp knife, cut through the baklava following the same diamond-pattern as before. Pour two-thirds of the syrup over the top. Set aside to cool completely, then cover and store at room temperature for one day, allowing the syrup to be absorbed. If the syrup has been entirely absorbed, pour the remaining syrup over the baklava. Keep covered, at room temperature, up to 2 weeks.
9. To serve, trim around the edges and discard the excess phyllo. Remove the baklava pieces from the pan, place them on a plate and use a fine grater to grate the whole pistachios over each piece. Serve at room temperature.