Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
In a large skillet over medium heat, cook the ground beef until browned, breaking it up with a spoon as it cooks.
Add the chopped onion and minced garlic to the skillet with the beef. Cook until the onion is soft and translucent, about 5 minutes.
Stir in the diced potatoes and carrots. Cook for another 5-7 minutes until the vegetables start to soften.
Add the frozen peas and Worcestershire sauce to the skillet. Season with salt and pepper to taste. Cook for another 2-3 minutes until the peas are heated through. Remove from heat and let the filling cool slightly.
Roll out the puff pastry sheets on a lightly floured surface. Cut each sheet into quarters to make 8 squares in total.
Spoon the beef and vegetable filling onto one half of each pastry square, leaving a border around the edges.
Brush the edges of the pastry with beaten egg, then fold the other half of the pastry over the filling to enclose it. Press the edges firmly to seal, then crimp the edges with a fork.
Place the pasties onto the prepared baking sheet. Brush the tops with more beaten egg for a golden finish.
