Preheat your oven. Set the temperature to 400°F (200°C) and allow it to heat up while you prepare the pizza.
Roll out the puff pastry. On a lightly floured surface, roll out the thawed puff pastry sheet into a rectangle or square shape, depending on your preference for the pizza's size.
Brush the puff pastry with the beaten egg. This will give the pizza a beautiful golden color when baked.
Add the pizza sauce. Using a spoon or spatula, spread an even layer of pizza sauce on top of the puff pastry, leaving a small border around the edges for the crust.
Layer the mozzarella cheese. Sprinkle the mozzarella cheese evenly over the pizza sauce, ensuring that the cheese reaches all corners of the puff pastry.
Add the toppings. Now it's time to get creative! Add your favorite toppings, such as sliced green peppers, mushrooms, red onions, black olives, baby spinach, and even a sprinkle of red pepper flakes if you like a little heat.
Bake the pizza. Carefully transfer the prepared puff pastry pizza onto a baking sheet lined with parchment paper. Place it in the preheated oven and bake for approximately 15-20 minutes, or until the puff pastry is golden brown and the cheese is melted and bubbly.
Once the puff pastry pizza is baked to perfection, remove it from the oven and let it cool for a few minutes before slicing it into desired portions. Serve it fresh out of the oven and watch as everyone indulges in the delectable flavors.