Prepare and chill Quick-Method Croissant Dough as directed.
To shape turnovers, cut the chilled dough crosswise in half. On a lightly floured surface roll each half of dough into a 12-inch square. Cut each square into nine 4-inch squares (18 squares total). Spoon about 2 teaspoons of the preserves onto the center of each square. Top with several pieces of the chopped strawberries.
In a small mixing bowl beat egg and water using a fork. Lightly brush edges of dough with some of the egg mixture. Fold squares in half to form triangles; seal edges with tines of a fork. Place the triangles 4 inches apart on ungreased baking sheets. Cover and let rise in a warm place until nearly double (45 to 60 minutes).
Brush turnovers with additional egg mixture. Bake in a 375 degree F oven about 15 minutes or until golden. Remove turnovers from baking sheets. Cool slightly on wire racks. If desired, sprinkle powdered sugar over warm turnovers. Serve warm or cool. Makes 18 turnovers.