These chocolate turnovers are at their best served warm.

Chocolate Turnovers

1 1/3 cups all-purpose flour 1 tablespoon granulated sugar 1/4 teaspoon salt 5 tablespoons vegetable shortening, cut up 4 tablespoons cold butter (no substitutes), cut up 3 to 4 tablespoons ice water 1 large egg yolk 2 ounces bittersweet or semisweet chocolate, finely chopped 2 ounces premium white chocolate, finely chopped 4 teaspoons granulated sugar - divided use

Pulse flour, sugar, and salt in food processor. Add shortening and butter; pulse until mixture resembles coarse crumbs. Add water through feed tube, 1 tablespoon at a time, pulsing until mixture begins to hold together but still is crumbly. Shape pastry into a ball and flatten into a thick disk. Wrap and freeze 15 minutes.
Meanwhile, arrange oven rack in lower third of oven.
Heat oven to 425°F (220°C). Line a cookie sheet with parchment paper. Beat yolk and 1 tablespoon water in cup. Set aside.
Divide pastry into 4 equal pieces. Working with 1 piece at a time (refrigerate remaining 3 pieces) on a lightly floured surface, roll pastry into a 6-inch circle. Sprinkle 1 heaping tablespoon each dark and white chocolate in center of circle, leaving a 1-inch border. Brush border with egg. Fold pastry in half. Seal edges with fingertips, then trim with fluted pastry wheel. Transfer turnover with a spatula to cookie sheet. Brush top with egg mixture; sprinkle with 1 teaspoon sugar. Refrigerate. Repeat.
Bake turnovers until golden brown, 16 to 20 minutes. Serve immediately, while warm.

Makes 4 turnovers.

Nutritional facts per serving: calories: 570, total fat: 39g, saturated fat: 17g, cholesterol: 84mg, sodium: 278mg, carbohydrate: 51g, fiber: 1g, protein: 7g.