Cooking Instructions:

Preheat the oven to 350°F (180°C). In a skillet, cook half of the chopped onion and minced garlic over medium heat until softened. Add the ground beef and cook until browned, breaking it up with a spatula.

Once the beef is fully cooked, remove it from heat and stir in the cream of mushroom soup and Worcestershire sauce. Season with salt and pepper to taste. Allow the filling to cool completely.

On a lightly floured surface, roll out the thawed puff pastry to a thickness of about 1/8 inch. Cut the pastry into sections, approximately 6x6 inches, depending on the desired size of your Wellingtons.

Place a portion of the cooled beef filling in the center of each pastry square. Fold the pastry over the filling, sealing the edges by pressing them together with your fingers or a fork. Brush the tops with the beaten egg to achieve a golden finish.

Arrange the sealed Wellingtons on a baking sheet lined with parchment paper. Bake in the preheated oven for 30-32 minutes, or until they're golden brown.

While the Wellingtons are baking, prepare the gravy. In a saucepan, cook the remaining chopped onion and garlic until softened. Whisk in a tablespoon of flour and gradually add beef stock, stirring constantly until thickened. Simmer for about 5 minutes and season with salt and pepper as needed.

Once the Wellingtons are done baking, remove them from the oven and let them cool slightly before serving with the homemade gravy.

For the best results, guarantee that the filling has completely cooled before wrapping it in the puff pastry to avoid sogginess. Lightly scoring the pastry can enhance the presentation and help it cook evenly. Feel free to experiment with different vegetables or herbs in the filling for added flavor.

Finally, remember that a good egg wash not only gives a beautiful shine but also helps the pastry develop a lovely crust. Enjoy your Beef Mince Wellington!