Preheat oven to 356°F (180°C).
Cut the puff pastry into 11x11 cm, then make a square frame using a knife. Place them on a baking tray lined with parchment paper. Poke the inside of the frame with a fork. Set aside.
Mix cream cheese, powdered sugar, and egg until well combined. Add heavy cream and vanilla essence, and mix again until well combined.
In a small bowl, beat the egg with milk, then brush the outer edge with an egg wash mixture.
Add 2 tbsp of the cream cheese mixture to the puff pastry then top it with blueberry. Bake for 30-35 minutes or until golden brown. Cool the blueberry cream cheese danish and just before serving, dust it with powdered sugar. Enjoy!.