Roll 1 puff pastry sheet into a 14- x 10-inch rectangle. Sprinkle with 1 cup Gruyère cheese. Roll both narrow ends of puff pastry sheet in to meet in center of rectangle.
Repeat procedure with remaining puff pastry sheet and Gruyère cheese. Cut each roll into 1/4-inch slices. Place slices on parchment paper-lined baking sheets; brush with melted preserves. Bake at 400° for 12 minutes or until golden. Serve warm.
Note: You can make these pastries ahead and freeze the uncut, unbaked rolls. Wrap rolls in heavy-duty plastic wrap, and freeze. To serve, let rolls stand at room temperature 10 minutes before slicing. Brush with preserves, and bake as directed.