Creating these amazing Cranberry Brie Bites is straightforward if you follow these simple steps:

1. Preheat Your Oven: Preheat your oven to 375°F (190°C).
2. Prepare the Puff Pastry: Roll out the puff pastry on a lightly floured surface to smooth out any creases. Cut the pastry into 2-inch squares.
3. Prepare the Brie: Slice the Brie cheese into small pieces, approximately 1-inch cubes.
4. Assembly Prep: Place a puff pastry square on a lined baking tray. In the center of each square, place a dollop of cranberry sauce and a piece of Brie cheese.
5. Add Optional Toppings: If desired, sprinkle chopped pecans and fresh rosemary over the cheese and sauce.
6. Crimp the Pastry: Fold the corners of the pastry squares over the filling towards the center, pinching them to seal tightly.
7. Apply Egg Wash: Beat the egg in a small bowl and brush the tops of each pastry with the egg wash for a golden finish.
8. Season: Lightly sprinkle sea salt on top of each bite.
9. Bake: Place the tray in the preheated oven and bake for 15 minutes or until the pastry becomes golden brown.
10. Cool: Allow them to cool for a few minutes on the baking tray before serving.

Following these steps, you will create an incredible batch of Cranberry Brie Bites that deceives even seasoned chefs!