250 g clarified butter or ghee (1 cup + 2 tbsp), melted
350 g shelled unsalted pistachios (2 1/2 cups), finely chopped
2 tbsp sugar
Syrup: 400 g sugar (2 cups)
300 ml water (1 1/4 cups)
1 tbsp lemon juice
Optional: 1 tsp rose or orange-blossom water
How to make it
Syrup first (10 min plus cooling): Boil sugar and water 8 minutes, add the lemon juice and simmer 2 minutes more. Cool completely (cold syrup on hot pastry keeps it crisp).
Nuts (2 min): Mix the pistachios with the 2 tbsp sugar. Keep 2 tbsp aside for the top.
Layer (25 min): Heat the oven to 170C (340F). Brush a 23 x 33 cm (9 x 13 in) pan with butter. Lay in 10 filo sheets, brushing each with butter (trim or fold to fit). Keep the rest under a damp towel.
Fill and top (10 min): Scatter the pistachios evenly. Top with the remaining sheets, buttering each one. Brush the top well.
Cut (5 min): With a sharp knife, cut all the way through into diamonds or squares before baking.
Bake (50 to 60 min): Bake until deep golden and crisp, 50 to 60 minutes.
Soak (4 hr): Pour the cold syrup over the hot baklava; it should sizzle. Scatter the saved pistachios. Leave uncovered at least 4 hours before eating.
Tips
Clarified butter browns without burning and keeps the layers crisp.