Pear, leek and gruyere turnovers

This recipe is from Bon Appetit via the Savory notebook. It is really really yummy. I used the spiral method as described in the savory notebook to utilize all of the puff pastry and because it seemed like less work. One recipe was not quite enough for a crowd, so I would recommend doubling the filling if you're cooking for more than four people.

2 tablespoons butter
1 1/2 cups chopped leeks
1 6-7-ounce firm but ripe pear, peeled, cored and chopped
1 1/2 teaspoons sugar
3/4 cup (about 3 ounces) grated Gruyere cheese, packed
1 1/2 tablespoons chopped fresh chives
1 17.3-ounce package frozen puff pastry (2 sheets), thawed
1 egg, beaten to blend (for glaze)

Melt butter in heavy large skillet over medium heat. Add leeks; stir 1 minute. Reduce heat to low; cover and cook until leeks begin to brown, stirring occasionally, about 7 minutes. Stir in pear and sugar. Increase heat to medium; sauté uncovered until any liquid evaporates, about 2 minutes. Season with salt and pepper. Transfer to bowl; cool. Stir in cheese and chives.

Place puff pastry sheets on work surface. Using a 4 1/2-inch-diameter tartlet pan or bowl as aid, cut out 4 rounds from each pastry sheet. Roll out each pastry round to 5-inch circle. Place leek mixture on half of each pastry round, dividing equally. Brush pastry edges with egg glaze. Fold pastry over filling, pressing to adhere. Press edges with fork to seal. Brush turnovers with egg glaze. Pierce pastry in several places with toothpick. Place on baking sheet. Chill 20 minutes. Preheat oven to 400º. Bake turnovers until puffed and golden, about 18 minutes. Serve warm.