- Flour, for dusting
- 1 sheet frozen puff pastry, from one 17-ounce package, thawed
- 2 small leeks (white and light green parts only), well rinsed, dried and thinly sliced (about 2 1/2 cups)
- 1/2 cup coarsely grated smoked Gouda cheese
- 1/4 cup freshly and finely grated Parmesan (use a microplane grater or the smallest holes on a box grater)
- Kosher salt and freshly ground black pepper
- 2 tablespoons finely chopped chives
1. Preheat the oven to 400 degrees F. On a lightly floured surface, roll the puff pastry to a 13-inch-by-10-inch rectangle and transfer to a parchment-lined baking sheet. Prick the pastry all over with a fork and scatter with the leeks and both cheeses. Sprinkle with a pinch of kosher salt and 1/4 teaspoon pepper.
2. Bake until the pastry is a deep golden brown and the leeks are tender, 25 to 30 minutes. Cool for 10 minutes. Garnish with the chopped chives, cut into 16 or 24 pieces and serve.