Leek, Prosciutto and Cheese Empanadas
From: Gourmet January 1994.
Makes 4 empanadas

The empanadas can be put together ahead of time and popped into the oven to bake just before serving.

3/4 cup chopped well-rinsed white and pale green part of leek (about 1/2 pound untrimmed)
2 tablespoons chopped sliced prosciutto or ham (about 2 thin slices)
1 tablespoon olive oil
3 tablespoons water
2 tablespoons grated Manchego cheese or mild white Cheddar cheese
1 sheet (about 1/2 pound) frozen puff pastry, thawed

an egg wash made by beating together 1 large egg and 1 teaspoon water

Preheat oven to 425°F.
In a small heavy skillet cook leek and prosciutto in oil over moderate heat, stirring, until leek is softened. Add water and cook, covered, over low heat until leek is soft, about 10 minutes. Pour off any excess water. Remove skillet from heat and add salt and pepper to taste. Let filling cool completely and stir in cheese.

Roll out puff pastry on lightly floured surface into a 12-inch square and with a 4-inch round cutter cut out 4 rounds.

Divide filling among rounds, mounding it in the center, and brush edges of rounds with water. Fold rounds in half, pressing edges together firmly, and crimp edges with tines of fork to seal well. Empanadas may be prepared up to this point 1 day in advance and kept covered and chilled.

Arrange empanadas on a dampened baking sheet and brush with egg wash. Prick top of each empanada several times with fork (for steam vents). Bake empanadas in upper third of oven until puffed and golden, 12 to 15 minutes.