Roll one puff pastry sheet into a 14" x 10" rectangle. Sprinkle with 1 cup Gruyère cheese. Roll each short side, jellyroll fashion, to meet in center. Repeat procedure with remaining puff pastry sheet and cheese.
Cut each roll into 1/4" slices. Place slices on parchment paper-lined baking sheets; brush with melted preserves. Bake at 400° for 8 to 10 minutes or until golden. Serve warm.
Make Ahead: 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 above.