Preheat your oven to 400°F (200°C).
Roll out the puff pastry on a lightly floured surface.
Cut the pastry into squares (about 3 inches each).
Place a piece of brie cheese in the center of each square.
Top the brie with a spoonful of cranberry sauce.
Fold the corners of the pastry over the filling and pinch to seal.
Brush the tops with beaten egg.
Place the bites on a baking sheet lined with parchment paper.
Bake for 15-20 minutes, or until golden brown.
Let cool slightly before serving and garnish with rosemary.
