Apple Strudel (Heather Hill)

1/2 pkg.(17.3 oz.) frozen puff pastry sheets (1 sheet), 1 egg, 1 T. water, 1 can (21 oz.) apple pie filling
Thaw pastry sheet at room temperature for 30 minutes. Preheat oven to 375°. Mix egg, water, beat well and set aside. Unfold pastry on lightly floured surface. Roll into 16" * 12" rectangle. With short side facing you, spoon pie filling on bottom half of pastry to within 1" of edges. Roll jellyroll-style. Place seam-side down on baking sheet, tuck ends under to seal, brush with egg mixture. Cut several 2" long slits 2" apart on top. Bake for 35 min.