Goat Cheese Turnovers with Smoked Salmon and Leeks

2 teaspoons olive oil
1 small leek, halved, thinly sliced crosswise
¼ cup whipping cream
½ cup (3 ounces) soft fresh goat cheese, at room temperature
2 tablespoons chopped fresh herbs (choose from thyme, dill, or oregano)
1 teaspoon finely grated lemon zest
½ teaspoon sea salt or kosher
salt
¼ teaspoon freshly ground pepper
1 sheet frozen puff pastry, thawed overnight in the refrigerator
3 slices thinly sliced smoked salmon, each slice cut crosswise into ¼-inch-thick pieces

Smoked salmon, leeks and goat cheese come together in a beautiful harmony.

Position a rack in the center of the oven and preheat the oven to 400°F.
In a small skillet, heat the olive oil over medium heat. Add the leek and sauté until soft, about 5 minutes. Add the whipping cream and simmer until the mixture is reduced slightly, about 5 minutes. Let the mixture cool.
In a medium bowl, mash the goat cheese with a fork. Stir in the leek mixture; then add the chopped fresh herbs, lemon zest, salt, and pepper. Stir to combine.
On a lightly floured surface, unfold the pastry sheet and lightly dust it with flour. Using a rolling pin, roll the sheet into a 12-inch square. Cut the dough into 9 squares. Put equal amounts of the filling (about 1 tablespoon) onto the center of each square. Top with equal amounts of the sliced salmon. Moisten the edges of a square with a fingertip dipped in water. Fold the dough over to form a triangle, gently pressing around the filling and pressing the edges of the dough together. Use the tines of a fork to crimp and seal the edges of the turnover. Repeat with the remaining dough squares. (You can fill and shape the turnovers up to 2 hours ahead of cooking. Cover the unbaked turnovers tightly with plastic wrap or brush them with melted butter before chilling.)
Place the turnovers on a baking sheet and bake until the turnovers are puffed and golden, about 15 minutes.
Transfer the turnovers to a cooling rack and cool slightly. Serve turnovers warm.