On a floured surface, unfold a puff pastry sheet and roll to 15-inches x 10-inches.Place on a greased baking sheet and bake for 12 min. (It will come out of the oven puffed but fall back to flat as it cools.)
Beat the cream cheese together with the sugar in a mixing bowl until fluffy. Add the egg and vanilla extract; mix until smooth and combined.
Spread the cream cheese mixture over the pastry leaving an inch border.
Spoon the raspberry pie filling evenly over top of the cheese mixture.
Roll out the second sheet of pastry to roughly the same size as the baked pastry and place it on top of the raspberry pie filling. Lightly press down the edges onto the bottom pastry. Brush milk on top and sprinkle with sugar.
Bake for 35 min. Remove from the oven and allow to cool.
Cut into 12 pieces: cut 6 squares, and then cut each square diagonally to make 12 triangles