1. Lay pastry on a lightly floured work surface. Using a pastry wheel or knife, trim pastry into a 9-by-12-inch rectangle. Then cut off four 1-inch strips: two from one short end and two from one long side. Set strips aside. (Rectangle should be 7 by 10 inches.) Transfer rectangle to a parchment-paper-lined baking sheet.

2. Pierce pastry all over with a fork; brush with egg. Lay pastry strips on edges to create a border. Trim strips to fit, overlapping at corners. Brush egg over strips and underneath ends to seal. Cover with plastic wrap; refrigerate 1 hour.

3. Preheat oven to 400 degrees. Sprinkle pastry with the sugar. Transfer to oven; reduce oven temperature to 350 degrees. Bake until shell is just golden and puffed all over, about 15 minutes. Remove sheet from oven. Using an offset spatula, press down on middle of shell (leave border puffy). Return shell to oven; bake until golden brown, about 15 minutes more. Transfer to a wire rack; press down on middle of shell again. Let cool completely.

4. Pour cream filling into shell. Spread out to border with offset spatula. Refrigerate until filling is set, about 30 minutes.

5. Arrange roses over filling. Fold leftover peeled-apple slices into ruffles, and fill in gaps. Refrigerate, covered with plastic wrap, until ready to serve, up to 6 hours.